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10 Must-Read Books about Africa from Best-Selling Author Tony Park
by TheReadingRoom
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Tony Park recently stopped by to talk about his novel The Delta, but we couldn't let him leave without asking about his reading recommendations for books on Africa. Check out his suggestions below.
From the jungles of Borneo, to the civil strife of Assam, to the black markets of Vietnam, Dr Tammie Matson continues her quest to help reduce the human-elephant conflict around the world.
In this follow-up to her bestselling memoir Elephant Dance, Tammie takes on the black markets of Asia determined to make a difference and break the chains of rhino-horn poaching and the illegal ivory trade.
Crisscrossing South Africa – and further afield – in a quest to understand the land and continent of his birth – Malan does time with an extraordinary cast of characters: from vigilantes and outlaws to beauty queens and truckers; from Sol Kerzner to Jackie Selebi; from JM Coetzee to the last Afrikaner in Tanzania. Malan's honesty, his unwavering support for the underdog, and the unique power of his prose, make him one of South Africa's most important writers.
The Land God Made In Anger – South West Africa-Namibia – has been governed by South Africa for decades, ever since German rule ended after the First World War. But German influence has remained strong. So when, a month after the Second World War ends, two German officers erupt from the sea along the infamous Skeleton Coast, escaping from a crippled U-boat, they are arriving on friendly territory. But who are they? Why have they come? Why do only two men escape from the submarine? And why does one of them immediately murder the other one on the shore? Read more >
Deneys Reitz was 17 when the Anglo-Boer War broke out in 1899. Reitz describes that he had no hatred of the British people, but "as a South African, one had to fight for one's country." Reitz had learned to ride, shoot and swim almost as soon as he could walk, and the skills and endurance he had acquired during those years were to be made full use of during the war. He fought with different Boer Commandos, where each Commando consisted mainly of farmers on horseback, using their own horses and guns. Commando describes the tumult through the eyes of a warrior in the saddle. Read more >
Bruce Curry is the leader of a mercenary band with the dubious support of three officers. His mission: To relieve a diamond-mining town cut off by the fighting and retrieve a priceless consignment of diamonds. Along the way, he meets a beautiful Belgian woman. Shermaine is a dream come true. But the rest of Curry's journey is about to become a living nightmare. Ranged against his ill-disciplined unit are bandits, guerillas, and hostile tribes that infest the land. In a sinister atmosphere of omnipotent evil, Curry fights to stay alive—and protect Shermaine, his one true love. But to do so, he must face another, even deadlier enemy: one of his own men… Read more >
A little girl waits alone to be picked up after ballet class—until an unmarked car approaches, and she is gone. But this little girl is the daughter of Police Captain Riedwaan Faizal. But suspended from the squad, he finds himself powerless. With nobody on his side, the captain turns to investigative journalist and criminal profiler Dr. Clare Hart. Clare knows that the odds of a child's survival dwindle with each passing minute. She knows that hiding her investigation from the police has its own dangers. But she will do anything to help a heartbroken father … even if it puts all their lives at risk. Read more >
Detective Benny Griessel he has trodden on too many toes over the years ever to reach the top of the promotion ladder, and now he concentrates on staying sober and mentoring the new generation of crime fighters — mixed race, Xhosa and Zulu. But when an American backpacker disappears in Capetown, panicked politicians know who to call: Benny has just thirteen hours to save the girl, save his career — and crack open a conspiracy which threatens the whole country. A potent, suspenseful thriller, and a brilliant portrait of life in the country that will host the 2010 World Cup. Read more >
In mid-2008, after thirty years of increasingly tyrannical rule, Robert Mugabe, the eighty-four-year-old ruler of Zimbabwe, met his politburo. He had just lost an election. But instead of conceding power, he was persuaded to launch a brutal campaign of terror to cower his citizens. Journalist and author Peter Godwin was one of the few observers to slip into the country and bear witness to the terrifying period that Zimbabweans call, simply, the Fear.
In apartheid South Africa in 1976, medical student Isaac Muthethe is forced to flee his country after witnessing a friend murdered by white members of the South African Defense Force. He is smuggled into Botswana, where he is hired as a gardener by a young American woman, Alice Mendelssohn, who has abandoned her Ph.D. studies to follow her husband to Africa. When Isaac goes missing and Alice goes searching for him, what she finds will change her life and inextricably bind her to this sunburned, beautiful land.
The great heart of Africa is dying. Joseph Mahoney, the last colonial commissioner in the spectacular Kariba Gorge, is there to witness the death throes. Somehow, he must also ease the birth pangs of the new Africa that will take its place. His companions are Samson, his Matabele servant, and Suzie, the girl he loves. But Mahoney and Suzie are drifting apart, and now Samson has been accused of murder. And all too quickly, it seems, the country is heading towrds a bloodbath of revenge.
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Back The Mets: Contract Year Pushes Coming?
I agree fully with you Dan. I keep hearing how we can't part with Duda because of his 30 home runs, even though he hits like 27 of them in a 3 week span while hitting .500. Yet almost all are against scrub pitchers and the rest of the year he is lucky to hit a buck fifty. Yet we want to get rid of a guy who came from a lousy team yet was hitting .285, leading the league in HR's and RBI's. Yeah let's get rid of that. I know he started slow with us but the last few weeks he really picked it up. I think he finally got comfortable. Hell, put him at 1B and get rid of Duda. His fielding can't be any worse.
Finally, someone else who see that Duda has value in only about 20-30 games a year. I like the guy generally, but his "valleys" are so painful compared to his "peaks" over the course of a season.
I'd rather keep Bruce, give Wilmer the 1B job, and re-sign Loney who is a solid LH back-up and terrific defender for late inning replacement work.
What to do with the OF if we keep everyone? Personally, I'd rather start Bruce in RF and perhaps platoon Curtis and Juan in CF. Curtis won't complain and he will get the rest he needs. And while I'd rather give Juan the full time job, I can't see in any way shape or form that Terry and Sandy six a $16MM player who has been a great soldier if not always a great performer. That leave Conforto the odd man out which is not necessarily the worse thing in the word … let him rake in Vegas and focus on recognizing breaking pitches, although I guess they don't break as much in the PCL! Invariably one of the other guys will get hurt, and Conforto will get his chance again … he just has to be ready.
My main concern outside of Familia's expected suspension is TdA.
BTW – Bruce was only a .265 hitter when he was traded to the Mets.
Well, I suppose I have now been officially labeled a Met geek, because I remember well listening to Bob Murphy on the radio describing with excitement rookie Mike Vail during that batting streak.
Like Bob, I agree with your well written piece. Bruce is a one-dimensional player, but that one dimension has value. The market is glutted with unemployed power hitting outfielders, so there is no need to rush. The dilemna for Alderson is that the Mets need a 3+ WAR player in RF and CF. The need to close the gap on the Nats. While Bruce has had some big years and is still in his prime, he is just as likely to put up a 1.0 WAR as a 3.0 WAR. Heck, last year he hit 30 HR in a bandbox and only put up a 0.9 WAR. Put him in the AL, where he can DH some of the time, and he is much more likely to put up a 2+ WAR and add value for $13 million. For my 2 cents, while Conforto is no sure thing, he is a safer bet to put up a 3+ WAR than Bruce is, for the Mets. I still wouldn't give Bruce away or hold off on bullpen acquisitions until he is dealt, but I don't have to deal with Jeff W. and his payroll rules.
Lastly, keeping Bruce as Duda insurance at 1B is even a bigger risk. While Bruce has only 26 innings at 1B in the bigs, the advanced metrics are horrible. And, with DW's weak arm possibly at 3B on a regular basis, Duda is clearly a better defensive option, and the Mets do not have the luxury to trade away any defense right now.
Getting the Os to take Bruce and a mid-level prospect for Brach would be optimal, as still could make sense for each team if the chips fall in the Mets' favor.
Agreed, except I'd take anything that might be useful for Bruce to avoid an outfield log jam, with porosity being it's main feature. The comparison with Staub is a bit flawed since Staub was a much better hitter, although neither was a good defender, with Bruce's leading the way downhill since his knee problems surfaced during the 2013 season.
Dave — not a big fan of the WAR sabermetrics … see how well that turned out for the Cubs on Heyward despite breaking their WS curse.
I agree that trading Bruce to the AL makes the most sense … the problem is … all the other GMs know that too! To your point, I don't want to give Bruce away just for budget relief … just because they signed Yoenis, it is clear that the Mets are still not a top big market team from an ownership standpoint.
Despite his crappy track record to signing FA relievers to major league contracts, Sandy is as much concerned about extending that streak than he is with exceeding the crappy owners' budget. A good team would have already bolstered the pen and get whatever good value they can get for either of Bruce or Grandy … but, neither should be given away, especially to a team in the NL East!
But, the bantied-about trade with the O's is perhaps the most sensible trade I've seen yet for Bruce … we see if that comes to fruition if the O's can sign one of the FA power bats or get Blackmon from the Rockies.
Great article and worthy of consideration.
Bruce has a .3 WAR for the past three seasons combined. Hard work for a guy with as many home runs as he has, but it points to the other massive deficiencies in his game. Staub by comparison had a 5.3 WAR in the three seasons leading up to '76. Bruce is a butcher in the field and a strikeout machine. Rusty at that point was also horrible in the field but one of the most disciplined hitters in the game and, in going to Detroit, was well-positioned for use as a DH.
I think we're comparing two very different players. I have minimal expectations for any kind of dramatic rebound from Bruce. Thus far, the market seems to concur.
Gregg – Fair to say that Bruce and Rusty are/were 2 different players, BUT, we are talking about a Mets team that remains starved for offensive despite the re-signing of Cespedes and a questionably healthy Walker. BUT, Bruce will be playing for a contract and (if the rest of the offense is healthy) he will not be "the man" … given both of these points, the former should drive him and the latter should relax him … he is a solid supporting role player and can thrive under the right circumstances … plus not all of his success has been because of the bandbox that is GABP in Cincy — check out his home/road splits.
However, I think the real question is: can he play well in the headlights of NYC? If he's not in the position of being "the man", I think he can thrive … if Cespedes and others are not healthy and/or don't produce, I think Jay will fail as well. But, to ignore 33 HRs and 99 RBIs (not all of which were produce in GABP) he produced last year despite the WAR metrics is a mistake. I think the other GMs just know that Sandy is looking to dump Jay and are trying to get Bruce as cheap as possible, especially given the outstanding glut of similar but slightly inferior options on the FA market.
No way does Bruce pull a Jason Bay next year if he remains with the Mets … no way does he "annualize" his 2016 Mets results to the tune of 24 HRs and a Granderson-like 57 RBIs in a full 2017 season and maintain a stat line of .219/.294/.391/.685 or have repeat of his 2014 season with the Reds … he may not repeat 33/99, but I'd take 25+/85+ from Jay … we shall see if he has that chance!
Gregg – I'd also like to add that while Jay Bruce is no gold glover and moves marginally better than Bartolo in the OF, he does have a pretty decent arm … that said, he does not have Cespedes' cannon either.
He's not very good. Judging both players purely on their offensive contributions, Staub was an above-average to excellent hitter in the two years leading up to his trade by both Baseball Reference and Fangraphs. Bruce was a below-average to putrid hitter in the two years prior to his white hot start to 2016 according to both sites. Notice that he hit only slightly better in the second half of 2016 than he did in 2014 and 2015. The Reds were hoping they could ride his hot start to the season to sucker some desperate team to give up something substantial for him before his luck ran out. Trading for Bruce made no sense at the time and keeping him makes less sense going forward.
Dave — I have no problem trading Bruce, but he should not be given away just to stay under budger or to create room to sign/trade for bullpen support.
As I responded to another fan, comparing Bruce and Rusty is not entirely fair … but, to simply get rid of Bruce without adequate return is a mistake … especially if he goes to a team like the Phillies.
As for trading for Bruce, Sandy was self-admittedly just hedging his bets in the event Cespedes was not re-signed. I wasn't a fan, but I wasn't against it either, all things considered. But, yeah, Sandy did not get the MVP-type lighting in a bottle that was Cespedes circa 2015.
What is adequate return. The Mets gave up nothing to get him. Is a low level prospect like Hererra not adequate???? You ain't getting a star for a guy it took the Reds two years to dump.
What is adequate return for 33 HRs and 99 RBIs? Before you or anyone say that he did most of that in the bandbox that is GABP, his road splits last season (in less than 80 games) were: 16 HRs 50 RBIs and a slash line of .261/.319/.525/.844. And, despite his crappy 1st month and 1/2 with the Mets, his BA w/ RISP AS A MET at .237 was still significantly higher than Granderson's and TdA's last year and higher than Duda's career BA w/ RISP at .236 as well as for his most recent "full" season in 2015 when he was at .219.
I'm not looking for a star, but for a Brad Brach if the O's didn't trade for a Seth Smith? Perhaps throw in another mid-level prospect?
Unfortunately, there are too many other "next tier" FAs that can probably be had for less than $13 MM a year and produce decent offensive numbers … just not 33 and 99.
I was opposed to the Bruce trade from the moment it came down, so there is a make chicken salad out of chicken sh&t aspect to this article.
But and be fair now, how many people here would be skewering Sandy and the Wilpons if they dump Bruce for next to nothing and watch as he puts up some career-norm numbers, while at the same time both Conforto and the Mets offense struggles?
Ideally, I'd like to see the Mets swap Bruce and Gabby Ynoa to Toronto for Dalton Pompey and Sean Reid-Foley, with the Mets eating some of Bruce's salary. It could still happen I suppose. I still like SD's Brad Hand, but the Mets would have to pick up almost all of Jay's salary for this to occur.
Sometimes these things have a way of working themselves out, but other times (see Davis, Ike) they don't.
It would have been far better if they just declined his option and paid the 1M to let him go and free up 12M in payroll. Bad trade, worse option move.
Dan C – if Bruce gets traded, especially if within the NL East, he will have a career year and burn the Mets … no question. But, if the Mets get adequate return in a trade, I have no problem trading him. I also have no problem keeping him.
I re-iterate my earlier comments — if he's not "the man" and Cespedes is healthy (as well other key players — although I don't expect much from DW) … I think Bruce will be fine as the Mets primary RF. However, if YC and other key guys get hurt, Bruce will struggle in trying to do too much offensively in the glare that is NY baseball and its media coverage.
Bruce didn't have to be the man on Votto's Reds, and still didn't produce much besides HRs.
I agree with you that the worst-case scenario is probably Bruce trying to do too much. But even the average-to-good scenario isn't one I'm enthused about.
The BEST-case scenario with Bruce is pretty awesome, though. It would be sad to see that play out with another team. I think that'll take more than just comfort, though — it'll take an entirely new approach to the strike zone, and a flatter swing (at least on some pitches).
He's no Cory Seager for sure, but I think he did more than just hit HRs … 33 HRs alone does not make 99 RBIs.
But, yeah, he's got lay off those bad off-speed pitches … he was definitely trying to hard with the Mets until the last 10 days of the season … and it messed him up mentally making his completely guess at the pitches thrown at him … he looked like he had no plan at the plate. But, except for 2014, Jay has not had a bad overall season. He's not a star of Cespedes' caliber, but again, he's a capable supporting cast member.
Bruce is basically Pedro Alvarez, who is struggling to find jobs despite leading the NL in HRs a few years ago. GMs pay less for rep and bombs-but-nothing-else than they used to. There is no way the O's are giving us Brad Brach for Bruce when they can just sign an Alvarez type.
I mean, MAYBE there are still a few dumb GMs out there, and maybe one of them panics as they enter spring training with a black hole in RF, and maybe their farm system is overflowing with relief prospects, and maybe at that point they give away their 8th inning guy to get Bruce. Anything's possible. Maybe waiting to see if that pans out is the best move for Sandy and co.
I completely agree with Dan on the risk with Conforto — I strongly suspect he's a bust, to be honest, as his 2016 struggles just went on too long — but I'd rather bet on Lagares than Bruce.
Especially because Collins is willing to move the young guys around, but will surely play Bruce every day if he has him. A Lagares-Conforto mix-and-match will probably hurt the team less.
If we start 2017 with Bruce, I will be rooting for a red-hot April and then a trade after the first game where he appears to be cooling off.
Conforto's 2016 struggles had a lot to do with his wrist, and their efforts to keep him on the field with cortisone injections in spite of obvious performance issues. Bust is always a possibility, but I think the opposite is more likely because of that injury, and the lack of regular PT post Bruce.
As for a red hot April, I wouldn't wait for the inevitable cold spell to unload him. Another consideration is the over 2M per month it will cost to keep him, not a good thing for the small market Mets.
I agree that Conforto had health and PT working against him, but I still have concerns. Probably the number one position player I'll be watching in spring training!
Re: the value of HRs, the Mets hit an absolute ton of them last year, but didn't score much because they were rarely on base. More Jay Bruce is NOT what this team needs.
The bench is Flores (UT), Reyes 2b-ss-3b, Lagares-cf, the backup catcher and either Nimmo or Conforto. If Bruce stays, my hope is that Conforto starts the year in AAA.
I don't hate that lineup, but it definitely takes on an all-or-nothing feel with the ball either leaving the yard or the batter turning right at first base. I don't anticipate any big trades shaking this arrangement up, and while we might see some call ups like TJ Rivera and perhaps even Amed Rosario, this is probably it, at least to start the year.
Dan – it's a pretty big IF that DW and Walker are healthy and fully ready to go on Opening Day given the kind of injuries they had. I assume they will not be and b/c of that, both Reyes and Flores will play critical roles at the start of the season.
The rest of the bench would be: TJ Rivera, Nimmo (b/c he can play all OF positions capably) and ideally, KJ, if they can get him to come back.
While I'd prefer to have Conforto play everyday, let him do so in Vegas and focus on laying off breaking balls out of the K zone, so that he's ready when one of the OFs invariably get hurt.
Will the Mets do what makes sense?
Hey, why do the Mets wait until late every year to acquire Kelly Johnson? Why can't they just sign him today?
Except I don't think we can rely on Reyes either. Even in his prime, he spent a lot of time on the DL. I keep coming back to the Toronto deal for Pompey. He might just be a somewhat faster version of Lagares, but the stolen base potential is there. If he can OBP (362) the way he has the last three years in AAA, he could definitely help the Mets out. Bruce for Pompey and Reid-Foley would make me very happy.
There are some indications that the Jays think Pompey won't hit in MLB. I think I'd rather go with the guy who might have been the best defender in baseball from 2013-2014. We really don't need more depth of risky/okay outfielders — we've got Nimmo!
I don't know much about Reid-Foley, but I do like the prospect idea. Maybe find someone out there who's got star potential but is blocked and will come cheaper than usual?
Argon — I have no confidence that Sandy and Terry will do what makes sense.
And, the latest is that the Braves will sign KJ again and then trade him to the Mets before the trade deadline for more of the Mets' farm system.
Why such a big deal over another over paid one dimensional player. The Mets gave up nothing to get him. Dillson Hererra, so bad he couldn't even earn a September call up to one of the worst teams around. The only ones who have him as a high level prospect are Met fans. You gave up nothing to get him, you'll get nothing to dump him. Two and half years of horrible hitting makes a one dimensional man worthless. Why trade for Bruce when you can have his clone Alvarez for a third of the cost and you don't have to waste time with Alderson.
If AB's notion about Pompey is accurate and the Mets do acquire him, then they will have essentially traded an offensively challenged middle infielder for an offensively challenged outfielder.
I think the key statement about Bruce was made to an unattributed Mets FO source. It was something to the effect that Jay was their insurance policy in the event Cespedes walks and that insurance can be costly.
The cost could very well be the portion of Bruce's salary they give to whomever takes him off their hands in return for Dilson Herrera II.
If Bruce was the insurance policy to replace Cespedes, it's a good thing they didn't have to file a claim on it.
Here is another potential landing spot for Bruce–the Oakland A's. In return the Mets get Ryan Madson. Right now, Oakland is looking at either Matt Joyce or Jake Smolinski in RF. Bruce would be an upgrade over both.
Madson, who saved 30 games last year is actually owed more money than Bruce is, albeit over a two-year period. Irony of ironies, the A's end up sending the Mets $ to balance the dough. The Mets may have to send Beane a lower-level prospect or two to sweeten the deal.
Not advocating this deal, but I wouldn't hate it. Just my attempt to keep the flickering embers of this year's hot stove alive.
Bruce was a hedge she we didn't know if La Potencia would stay. Im for trading him for value but not for giggles.


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Is Arctic Ice Loss Driven by Natural Swings?
March 15, 2017 Natural VariabilityAMO, Andrew Shepherd, Anthony Watts, Axel Schweiger, Carbon Brief, Daily Mail, David Middleton, Ed Hawkins, Eric Steig, Mark Morano, Qinghua Ding, Reuters, Roz Pidcock, William ConnolleyJim Hunt
An interesting new paper on Arctic sea ice has just been published. According to the conclusions of "Influence of high-latitude atmospheric circulation changes on summertime Arctic sea ice":
Although positive feedbacks between sea ice and the Arctic circulation exist, we find that these are small during summer. Instead, circulation variations over the Arctic have been a significant factor in driving sea-ice variability since 1979, and have had a non-trivial contribution to the total surface temperature trend over Greenland and northeastern Canada39 . The potentially large contribution of internal variability to sea-ice loss over the next 40 years reinforces the importance of natural contributions to sea-ice trends over the past several decades. The similarity of high-latitude circulation variability associated with sea-ice loss to the teleconnections with the tropical Pacific suggests a contribution of sea-ice losses from SST trends across the tropical Pacific Ocean. Decadal trends in the hemispheric circulation are an important driver of Arctic climate change, and therefore a significant source of uncertainty in projections of sea ice. Better understanding of these teleconnections and their representation in global models under increasing greenhouse gases may help increase predictability on seasonal to decadal timescales.
As you may already be able to imagine, this paper (PDF as submitted) is already the source of considerable controversy! Firstly let's take a look at an overview of the paper from the University of Washington, entitled "Rapid decline of Arctic sea ice a combination of climate change and natural variability":
"The idea that natural or internal variability has contributed substantially to the Arctic sea ice loss is not entirely new," said second author Axel Schweiger, a University of Washington polar scientist who tracks Arctic sea ice. "This study provides the mechanism, and uses a new approach to illuminate the processes that are responsible for these changes."
[First author Qinghua] Ding designed a new sea ice model experiment that combines forcing due to climate change with observed weather in recent decades. The model shows that a shift in wind patterns is responsible for about 60 percent of sea ice loss in the Arctic Ocean since 1979. Some of this shift is related to climate change, but the study finds that 30-50 percent of the observed sea ice loss since 1979 is due to natural variations in this large-scale atmospheric pattern.
Now let's take a look at another overview of the paper, this time from Roz Pidcock at Carbon Brief and entitled "Humans causing up to two-thirds of Arctic summer sea ice loss, study confirms":
Rising greenhouse gas emissions are responsible for at least half, possibly up to two-thirds, of the drop in summer sea ice in the Arctic since the late 1970s, according to new research. The remaining contribution is the result of natural fluctuations, say the authors.
The paper, published today in Nature Climate Change, confirms previous studies which show how random variations in the climate have acted to enhance ice loss caused by rising CO2.
Importantly, the authors state clearly in the paper that their work does not absolve human activity as a driver of Arctic sea ice loss. A News and Views article that accompanies the paper, by Dr Neil Swart from Environment and Climate Change Canada, adds:
"The results of Ding et al. do not call into question whether human-induced warming has led to Arctic sea-ice decline — a wide range of evidence shows that it has."
There has already been much debate about the paper on Twitter! Here's the "scientific" edition:
[View the story "Is Arctic Ice Loss Driven by Natural Swings? Scientific Edition." on Storify]
and here's the "skeptical" edition:
[View the story "Is Arctic Ice Loss Driven by Natural Swings? "Skeptical" Edition." on Storify]
Needless to say Anthony Watts swiftly stepped up to the plate on the "skeptical" side of the "debate" with a guest article on his blog by David Middleton entitled "Arctic ice loss driven by natural swings, not just mankind: study" which begins by quoting a similarly titled Reuters article by Alister Doyle:
FILE PHOTO: An undated NASA illustration shows Arctic sea ice at a record low wintertime maximum extent for the second straight year, according to scientists at the NASA-supported National Snow and Ice Data Center (NSIDC) and NASA. NASA/Goddard's Scientific Visualization Studio/C. Starr/Handout via Reuters/File Photo
Natural swings in the Arctic climate have caused up to half the precipitous losses of sea ice around the North Pole in recent decades, with the rest driven by man-made global warming, scientists said on Monday.
The study indicates that an ice-free Arctic Ocean, often feared to be just years away, in one of the starkest signs of man-made global warming, could be delayed if nature swings back to a cooler mode.
Natural variations in the Arctic climate "may be responsible for about 30–50 percent of the overall decline in September sea ice since 1979," the U.S.-based team of scientists wrote in the journal Nature Climate Change.
David embellished his article with some "humorous" asides such as:
"This is the worst of the worst catastrophes in the world! Oh, it's crashing … Oh, the humanity! Honest, I can hardly breathe. I'm going to step inside where I cannot see it."
Please say it ain't so!!!
"The melt of the Arctic is disrupting the livelihoods of indigenous peoples and damaging wildlife such as polar bears and seals while opening the region to more oil and gas and shipping."
Eskimos, seals and polar bears!!! Oh My!!! And more oil and gas shipping!!! Aiiieeee!!!!
which some of us took exception to:
David – An Arctic indigenous person of my acquaintance asks me to tell you to "go f(r)@ck yourself"!
What should I reply on your behalf?
No answer has yet been received to that (im)pertinent question!
All this excitement in the Twittosphere and elsewhere leads one to wonder whether Ding, Schweiger et al. saw (or should have seen?) all this coming, and if so what might have been done differently? In any event this story is set to run and run and run and……
[Edit – March 18th]
I tried this Google search this morning:
38,000 results. We're number 4. If you repeat the exercise please feel free to experiment with the search phrase(s) you employ. Make sure to only click on the link that leads you back here!
Alternative Points of View – Scientific
William M. Connolley (AKA Stoat)
Without being able to pick any obvious holes I feel somewhat uncomfortable with that; the idea that September ice depends just on JJA circulation doesn't feel at all right. Having decided that, though, they then run a variety of model experiments, for example "nudging" the circulation back to re-analysis, with and without an ocean-ice model underneath. And the result seems to be that it is mostly the circulation forcing the sea ice, rather than the sea ice changes forcing the atmosphere. This kinda-fits the "information flow" meme from way back so I should be prepared to accept that mostly. Having done that they then convince themselves that most of the circulation changes that matter to the ice are not GW forced, and so must be natural variability; and hence the conclusion. If you took all of this at face value then they'd have solved one of the puzzles, that on the whole models show much less ice decline that reality. But of course if the decline is substantially a freak of variation, not forced, that would fit.
The flaw in this overall, without looking at the details, is that it's hard to see a near-40-year trend and being so much natural variability. That seems to be asking for an awful lot of one-way variation.
The Science Media Centre
Prof. Andrew Shepherd, Director of the Centre for Polar Observation and Modelling at the University of Leeds, said:
"According to this new research, the dramatic decline in Arctic sea ice that we have witnessed over recent decades is primarily due to anthropogenic (man-made) climate warming.
"Although this finding may not come as a surprise, being able to separate this from the effects of natural climate variability is an important step forwards, and paves the way for an improved understanding of what we should expect in future decades."
Dr Ed Hawkins, Climate research scientist at the University of Reading, said:
"Recent summer Arctic sea ice extents have all been amongst the lowest on record but this is not necessarily all due to warming global temperatures – part of the sea ice decline is also because of changes in the atmospheric circulation.
"It is challenging to determine how much of the change in the circulation is itself due to warming temperatures, but this study suggests that a substantial fraction is due to natural fluctuations.
"Looking ahead, it is still a matter of when, rather than if, the Arctic will become ice-free in summer, but we expect to see periods where the ice melts rapidly and other times where it retreats less fast."
Archived Alternative Points of View – "Skeptical"
Colin Fernandez at the Daily Mail
HALF of Arctic ice loss is driven by natural swings and not global warming, controversial study claims
Decline in ice cover due to 'random' and 'chaotic' natural changes in air currents
The rest has been driven by man-made global warming, scientists said
Colin Fernandez' Daily Mail article reproduced at the "Global Warming Policy Forum"
The Arctic icecap is shrinking – but it's not all our fault, a major study of the polar region has found. At least half of the disappearance is down to natural processes, and not the fault of man made warming.
Part of the decline in ice cover is due to 'random' and 'chaotic' natural changes in air currents, researchers said.
The rest has been driven by man-made global warming, scientists said.
The research means that although it is widely feared that the Arctic could soon be free of ice, this could be delayed if nature swings back to a cooler cycle.
Colin Fernandez' Daily Mail article reproduced at Mark Morano's "Climate Depot"
Study in journal Nature: HALF of Arctic ice loss driven by natural swings — not 'global warming'
David Middleton at Anthony Watts' "Watts Up With That"
From the No Schist, Sherlock files…
Perspective: NSIDC Arctic Sea Ice Index Interactive Graph
The five earliest years of data plot near +2 standard deviations. The five most recent full years of data plot near or just outside of -2 standard deviations. Ding et al., 2017 conclude that up to half of the difference is due to the NAO and other natural climate fluctuations.
Paul Homewood at "Not a Lot of People Know That"
Shock news! Scientists discover natural climate cycles.
Astonishingly though, the study makes no mention of the Atlantic Multidecadal Oscillation, which also has a significant effect on Arctic sea ice extent.
Since the late 1970s, the AMO has moved from the coldest point of its cycle to its highest, coinciding with a decline in Arctic sea ice coverage.
Patrick Michaels and Paul "Chip" Knappenburger at "The Cato Institute":
Considering that the climate models are already performing poorly as it is, the new finding means that they are actually faring even worse than has been generally realized. And accounting for this strengthens the case for a lukewarming future from greenhouse gas emissions.
Ring up another strike against the climate models, and another reason why basing government policy on their output is a bad idea.
← Shock News! Finally, the GWPF Corrects a Mistake!!	That Deaf, Dumb and Blind Kid Sure Plays a Mean ClimateBall™ →
23 thoughts on "Is Arctic Ice Loss Driven by Natural Swings?"
Aaron Lewis says:
I was very disappointed when I discovered that a virgin, with a fresh bay leaf in her mouth, could tell a falsehood. I was even more disappointed when I discovered computer models were even more at the mercy of of their "priests", than the virgins at the Temple of Delphi.
All models are wrong, some are useful, some will save your life. CMIP5 is like a virgin with a fine, large bay leaf in her mouth. She will speak nonsense if asked the wrong question.
Suggested Questions:
1)Has AGW changed global atmospheric circulation patterns?
2) Do AGW induced atmospheric circulation patterns allow more (latent) heat into the Arctic?
My favorite virgin is sitting under the bay tree muttering things that sound like, "AGW is very noisy." In the best Delphi tradition, it does not answer either of the questions, and yet it answers the big question; Does increased forcing of a large feedback system with multiple feedback loops including significant "lags" and "stores" increase the noise? It does, and we have known this since "Industrial Dynamics" by Jay Forester.
With AGW, I would expect to see more intense storms, more intense decadal variations such as El Nino, and more intense multi-decadal oscillations. In short, higher levels of "natural variation" are indicative of higher levels of AGW.
Tommy Barlow says:
What does this article in Nature say? I can't access it.
From the abstract and what I read here, it seems to be saying 'warming can come from the Pacific."
yah?
The oceans are warming.
Tommy – See the new PDF link above. From the introduction:
In this paper, we examine the contribution of the atmospheric circulation to Arctic sea-ice variability by utilizing an atmospheric general circulation model (ECHAM5) coupled with a simple ocean–sea-ice model in which the atmospheric circulation field is nudged to observations. Specifically, we explore how the high-latitude summertime atmospheric circulation impacts the September Arctic sea-ice extent, and estimate to what extent changes in atmospheric circulation explain the observed sea-ice loss of the past few decades.
In a bit more detail:
To examine the physical linkages, we focus on the connection between September sea-ice extent and the preceding summer (June–July–August, JJA) atmospheric circulation. We choose this preceding 3-month window because sea-ice extent anomalies have a ∼3-month decorrelation timescale , and previous studies have shown a strong link between summer circulation and sea-ice variability. We focus on physical mechanisms, analysing temperature, humidity, and downward longwave radiation (DLR), all of which are affected by atmospheric circulation and, in turn, affect sea-ice concentration. A key player is the radiation balance, which dominates the surface energy balance controlling the growth and melt of Arctic sea ice.
I suppose one's first question "of substance" might well be is "a simple ocean–sea-ice model" up to the task in hand?
Thanks Jim. I'll look at this paper in more detail later, but at first glance, it seems to verify GW effect on Arctic. It's a fascinating paper in so many ways though. I can't see the interpretation the deniers are giving it, and I can't see how the researchers can call those natural variations in the troposphere. Everything I ever read is that the poles are warming fastest. Probably because the heat of the overall atmosphere gets shunted there by planetary dynamics (eg. maybe the shape, the spin, the flatter poles), via the 'atmospheric circulation'.
Also, the jet stream is said by many to be changing. That may be tied to El Nino, a natural variation, but many predict El Nino's will change in frequency of occurrence due to GW.
…. and so on.
Matthew Greenwood says:
Climategate 3 !!! Wrote in ASIF earlier that I reckoned the greatwhitecon would be disturbed from its lair by trollish noises in cyberspace.
The Daily Fail was fairly quick off the mark Matthew. See the "Skeptical" slideshow above.
Whether their ace investigative fantasy fiction writer has anything to add over the weekend remains to be seen! In the meantime please also see our overview of the usual suspects:
https://greatWhiteCon.info/2017/03/is-arctic-ice-loss-driven-by-natural-swings/#AltDenialist
Chris Reynolds says:
Just got the time to review sea ice. I notice that Cryosphere Today is down and has been for ages. Do you remember what sea ice index we used for our bet, was it Cryosphere Today? I have a feeling it was 1 million kmsq for that index.
Welcome Chris,
Long time no hear, speak or see! How's things in your neck of the woods?
This is the relevant link I think:
https://greatWhiteCon.info/2015/05/the-new-normal-in-the-arctic/#comment-209391
Our wager does indeed seem to have been "that CT Area will drop to below 1M km^2 on any day before 2022."
I did discuss the possibility of CT disappearing before 2022 in the context of my parallel bet with "Chilly":
Do you anticipate spending more time back on the sea ice theme in the coming weeks? I note that the "Slow Transition" thread at the ASIF seems to have burst back into life recently, for example.
Hello Jim,
I'm very sorry for not getting back promptly. Work is hectic right now.
At present I am experiencing Critical Slowing in my laboratories and constantly fighting fire amidst a background of sharply increasing workload and poorly skilled graduates applying every time we advertise. The chances of my returning to sea ice this year are slim.
Anyway I have posted this comment with the email address I most commonly use now (which is on my phone and laptop).
I recall proposing an asymetric bet, if I lose I pay £1k if you lose you pay £1. Do you want to make it symmetric?
I'd prefer to use NSIDC since the probability of them going down is minimal. But whilst I can calculate are on a daily basis (which covers Wipneus stopping) I am hampered by what masks they are using, with area the effect is substantial.
What is your confidence on a <1 million for the month of September as per NSIDC Sea Ice index?
Or would you accept Extent?
Daily extent is available for Sea Ice Index
ftp://sidads.colorado.edu/DATASETS/NOAA/G02135/north/daily/data/
Area is only available as monthly
ftp://sidads.colorado.edu/DATASETS/NOAA/G02135/north/monthly/data/
I have moved the link to this page to the top so I don't get too busy and forget this time. (and ticked to notify comments by email)
litesong says:
Lead author Qinghua Ding has signed on past papers with Willie (oilcan) Soon, $1+ million exxon PR propaganda recipient, for services rendered. Soon-directed Q.D. has been looking for "natural causes" for years… & AGW denier liar whiners found themselves "a new scientist" to tote the AGW denier liar whiner ball. Hope Soon is nicely retired, so exxon can give Q.D., $2 million…. gotta keep up with inflation, ya know.
Qinghua Ding has indeed been listed at the top of the same paper as Willie Soon:
http://journals.ametsoc.org/doi/abs/10.1175/2008JCLI2353.1
However correlation doesn't necessarily equal causation! According to a comment over at Stoat:
Sometimes we can take guilt-by-association suspicions a little too far. Qinghua and I recently were co-PIs on an NSF proposal and I have no reason to suspect that he is anything but the careful and imaginative large-scale dynamicist that he appears to be.
As I pointed out over there:
Surely you're not suggesting that the likes of Axel Schweiger (of PIOMAS fame) and Eric Steig would somehow allow their strings to be pulled by Big Willie?
I ran a relevant Google search this morning. The results of my research are displayed above.
If you repeat the exercise please make sure to only click on the link that leads you back here!
DrTskoul says:
Very consequential high internal variation needs a very high climate sensitivity to forcings. Kinda the opposite of what we need. I don't know why the deniers are cheering… talking about a dumb bunch..
They're dumberer than dumb Doc.
IMVHO of course!
Rob Dekker says:
Apart from the fact that denialists misrepresent scientific papers all the time, in this case (Ding et al 2017) the paper itself is flawed.
There is no evidence (from the paper) that ANY part of Arctic sea ice decline is caused by "natural variability".
The only conclusion we can draw from the paper's findings is this :
60% of Arctic sea ice reduction is caused by summer-time climate change, while 40% is caused by climate change over the remaining 9 months.
Which is a very interesting conclusion by itself.
Please see my argument here :
http://scienceblogs.com/stoat/2017/03/15/influence-of-high-latitude-atmospheric-circulation-changes-on-summertime-arctic-sea-ice/#comment-58495
Jim, since you asked (in William Connolley's "stoat" thread to entertain a discussion about the issues with Ding et al 2017, here is my best summary of the problem with that paper :
I think it was Steven who correctly pointed out that there are TWO parts to Ding et al's claims of influence of "internal variability" on Arctic sea ice :
(1) about 60% of the September Arctic sea-ice extent decline since 1979 is caused by trends in summertime atmospheric circulation.
(2) about 70% of those atmospheric circulation trends is caused by internal variability (and hence the remaining 30% is anthropogenic).
Now the problem I have with the paper are very clearly in point (1) :
It started with Ding et al claim in the abstract of that point :
Here, we present evidence that trends in summertime atmospheric circulation may have contributed as much as 60% to the September sea-ice extent decline since 1979.
In my previous post, I noted that Ding et al uses "GL-Z200" (geopotential height at 200 mb, over Greenland) as their metric for "atmospheric circulation" over the Arctic.
That immediately means that the conclusion should have read something like this :
Here, we present evidence that trends in summertime geopotential height may have contributed as much as 60% to the September sea-ice extent decline since 1979.
Now, this should raise some eyebrows here and there, since geopotential height is clearly directly correlated with temperature. If the temperature goes up, so does geopotential height.
In fact, the ideal gas law (PV=nRT) DICTATES that geopotential height goes up with temperature.
Which is sustained in the ERA data set, where Ding et al itself reports that there is a R=0.94 correlation between geopotential height and temperature.
So AGW, which is certainly a part (if not all) of the trend in temperature over the Arctic is certainly also a part (if not all) of the trend in geopotential height.
And thus Ding et al 2017 can no longer claim that the Z200 trend (which they call "atmospheric circulation trend") is a source of "internal variability".
The even bigger problem with the paper is in which they determined the influence of "atmospheric circulation" (oops, I mean geopotential height) on Arctic sea ice decline.
If you want to investigate that influence with a sea ice/climate model, you would run the model with the ERA climate parameters, and compare it with a run that has geopotential height adjusted (subtract the geopotential height anomalies from the ERA data).
But that is not what Ding et al did.
They adjusted ALL variables (geopotential height, temperature, moisture content, downwelling LW radiation etc), essentially making the 'climate' constant.
Specifically, this is described here in the paper :
Exp-6: Same as Exp-5 except that the atmospheric forcing is modified to excise the forcing associated with the trends in the Greenland circulation pattern. To remove the circulations trend from the observat ions, we first construct the thirty-six-year seasonal (JJA) averaged time series of the Z200 index over Greenland, Z200 GL (GL-Z200 in Fig. 1c). We then linearly regress a key variable B
against this time series to obtain spatial pattern β(x,y) of the variable associated with the Greenland circulation index. Specifically, for the variable B we have
B(x, y, t) = β(x, y) × Z200 GL (t) (1)
where B represents a forcing field (for example, 10 m zonal wind, DLR, temperature, and so on), x and y indicate the location, t indicates time (JJA), Z200 GL is the Greenland Z200 index (GL-Z200 in Fig. 1c), and β is the regression coefficient. In the second step, the seasonal mean anomalous value of each forcing field is subtracted from the observed daily (or 6-hourly) forcing data during the summer—rendering a modified forcing that does not include variability or trends in variables that are asso ciated with Z200 GL. In the nine non-summer months, the forcing is exactly the same as that used in the Exp-5 control experiment. Given a strong correlation between circulation and surface winds, temperature, specific humidity, sea-level pressure, and downwelling long wave radiation in the Arctic, variability and trends in these six variables that are associated with Z200 GL are processed and removed from the forcing. The initial states of ocean, sea ice and atmosphere in Exp-5 and Exp-6 are exactly the same.
I highlighted in bold the section that describes that indeed they adjusted ALL variables to the extent that they linearly associate with Z200 GL. And because the correlation between all these variables and Z200 is very high (see figure 1c in the paper), they effectively eliminated ALL trends in ALL variables from their Exp-6 run, which means they effectively made the climate constant in that run.
Since the climate did not change in that run, they obtained a much lower ice melt rate.
Essentially the conclusion should thus have been :
Here, we present evidence that trends in summertime climate change may have contributed as much as 60% to the September sea-ice extent decline since 1979.
Which means that (this experiment 5 versus 6 suggests that) :
Which is an interesting conclusion, but as you can see it has NOTHING to do with ANY sort of "natural variability", so Ding et al cannot use it in their variability conclusion either.
You can still choose not to believe that this paper is seriously flawed, but you can no longer claim that you did not know.
I have emailed the authors Qinghua Ding, Eric Steig and Axel Schweiger for an opinion on my criticism of their paper.
Thanks for expanding on your analysis here Rob.
Nobody has responded to my own much more succinct query yet either:
Is "a simple ocean–sea-ice model" up to the task in hand?
Perhaps I should have emailed the authors too, rather than merely "tweeting" in their direction?!
Controversy @Twitter over natural variability & #SeaIce decline! https://t.co/Ds5crlfE8z Meanwhile in the #Arctic: @AxelSchweiger @ericsteig pic.twitter.com/fK5gUrlTdq
The choice of models in Ding et al 2017 is not that important.
First of all, they are not trying to predict sea ice extent absolutely.
They are running 'difference' experiments (such as the important Exp-5 – Exp-6 difference). A bit of uncertainty is not a big deal.
Secondly, the attribution of "natural variability" they report is 30-50%, which already is pretty wide. Using better models may tighten that a bit but that's all.
Finally : the REAL problem with Ding et al 2017 is not in the models. It's in the "method" they use, and the (implicit) assumptions they are making about how much of the geopotential height anomalies (and their trend) is "natural" and how much is "anthropogenic".
Rob – Sea ice modelling is of course a hobby horse of mine!
It seems to me that even the latest and greatest sea ice models fail to keep up with the rate at which the ice is thinning and fragmenting and hence becoming more mobile. The latest research suggests mixing with deeper, warmer water is occurring too.
How do those sort of "feedbacks" feed into the "natural" versus "anthropogenic" debate?
Jim, if you look at the details, Ding et al 2017 does not distinguish between "natural" versus "anthropogenic" climate change trends. Here is my post on William Connolley's "stoat" site, in a reply to Eric Steig (one of the authors of Ding et al 2017) :
William mentioned that "The point of the trend in z200 is "natural variability" is indeed the point that RD is questioning" and that is certainly a point of concern. After all, we KNOW that at least a part of the atmospheric temperature increase is due to AGW, which MUST have put an imprint on geopotential height over the Arctic. Jennifer Francis theory of wavy jetstreams due to reduced geopotential height difference between the tropics and the Arctic is based on that. Are you now saying that that theory is wrong ?
If not, then at least a part of trend in geopotential height increase (Z200) since 1979 must be anthropogenic.
But in fact the core of my argument goes one step further :
I claim that your "regression coefficient" in Experiment 6 eliminates ALL trends, natural or anthropogenic. And thus, that you essentially kept the climate constant in Experiment 6.
To see that, check the regression formula you use for Exp-6 :
Here, β(x, y) is the regression coefficient between Z200-GL and the variable under consideration, and B(z,y,t) is the "forcing" that you later subtract from the ERA data during summer.
Now, the regression coefficient is very good in finding trends.
So even if the correlation of Z200-GL and the variable (say "temperature") is not very good (like further away from Greenland) the regression coefficient will still find a 'trend', and thus the "forcing" you subtract for Exp-6 will still be pretty darn close to the linear relation we expect to see from the ideal gas law.
Qinghua has all the data available, so could you please ask him to reproduce the "adjusted forcing" for Exp-6 for, say the temperature variable north of 70deg, and check if it still has a trend since 1979 ? I claim it doesn't, since the regression method eliminated it.
And that means that all you have calculated (between Exp-5 and Exp-6) is the influence of climate change over the JJA period (60%) which means the remaining 40% was caused by climate change over the other 9 months.
Which is an interesting conclusion, but positively doesn't have anything to do with "natural" or "anthropogenic" causes of the trend in Z200-GL.
I reproduce here a comment by Rob Dekker over at Stoat:
Thanks to 'Steven' at the ASIF, I realized that I don't need to do a full ERA data download and a gridded regression analysis to test how much of the trend in summertime temperature and LW is taken out by Z200 changes if we apply the Ding et al 2017 regression method.
We can get a pretty good estimate by using the data from fig1c and run the numbers. I did that today, and indeed it shows (just like Qinghua already told me) a 35% residual trend for LW. Temperature shows a similar (35%) residual trend.
So, even though I find it difficult to accept that 65% of the trend in summertime Arctic temperatures would be caused by 'atmospheric circulation' (natural variability), leaving only 35% for AGW, I do understand the mistake I make and I (humbly) apologize to Qinghua and Eric for my arrogant stand in the issue.
I also reproduce a comment by Qinghua Ding on the Arctic Sea Ice Forum:
Many thanks for all your interesting/burning/critical/constructive comments and questions on our paper and my thoughts.
The first thing I want to say is that no one should expect that our short paper could fully address the most challenging question we are facing now in the polar community.
I am 100% sure that the mechanism of that "polar heat wave idea" is correct, since this is the only way ( in my personal view) to explain everything ( "everything" here means changes in sea ice, winds, temperature, vertical velocity and radiation fields) that we have observed in the Arctic since 1979. If we only considered CO2 forcing, it always puzzled me that some observed features in the Arctic cannot be well supported by either model results or dynamics of the Co2 greenhouse effect. But I have to say that we didn't consider aerosol in our work.
That 40% contribution from natural forcing is what we concluded based on the facts of our modeling experiments and a IPCC/NCAR model evaluation task.
In the paper, we used three steps of experiment/evaluation to reach to this number.
A. the first set of experiments
model: ECHAM5 with a simple ocean/sea ice:
to determine the direction of causality of observed connections between the circulation and all other variables.
1. the experiments qualitatively prove that the observed circulation change is important to regulate all other variables
2. and these atmospheric changes in JJA cannot be explained by sea ice melting if we only put Arctic sea ice decline in the model
B. IPCC/NCAR models evaluation
purpose: to consider whether forced responses of models to CO2 forcing can explain some observed features and understand how much the observed circulation change is still forced by CO2 forcing
Conclusion: we found that CO2 forcing cannot reproduce some features in the observation and only a part of the circulation change in the arctic is due to CO2 .
C. the third set of experiments:
model: a more sophisticated sea ice and ocean model ( a part of CESM) without atmosphere.
purpose: quantify how much of sea ice melting is due to the circulation change
conclusion: circulation related forcing at the interface between sea ice and atmosphere can substantially melt sea ice
This is our strategy to tackle the problem. I think this is not the perfect one but the best one we could come up with by using available in-house tools. As I know, our study is the first one to use a numerical model to tease the influence of the circulation on sea ice apart from other influences. So I think it is an important step forward to open up a new direction to understand arctic sea ice.
In the paper ( the first paragraph in the conclusion part), we acknowledged this limitation.
"Our conclusions are based on experiments involving several models rather than one integrated model. POP2-CICE4 simulations are used to allow for a realistic simulation of sea-ice variability, while ECHAM5 simulations allow for realistic simulations of the linkage between circulation and thermodynamic drivers of sea-ice loss, while permitting nudging to observed wind fields. The close agreement of patterns of thermodynamic forcing on sea ice between the ECHAM5 and POP2-CICE4 provides confidence in combining these two tools."
another part in the paper to discuss a possible way to improve our understanding
"Therefore, a substantial contribution of tropical Pacific variability on sea ice loss via this teleconnection is to be expected. A further examination of this
question will require a modelling framework that reproduces the tropics high latitude linkage faithfully and efficiently."
In my current work, I am working on a new project to repeat the experiments using a fully coupled model. That means combining sets A and C together into one integrated experiment to understand how the recent wind changes influence sea ice. I am sure with this better approach, we will move closer to the real contribution of natural forcing on sea ice melting but I still wouldn't say that I am 100% sure that the new number is correct because we never know whether another model would give the same number.
All of which goes some way towards answering my first "technical" question!

redpajama_set_name: RedPajamaCommonCrawl


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text:
Forums > Teacher Time Out > Teacher Time Out >
Discussion in 'Teacher Time Out' started by scholarteacher, Jun 16, 2009.
scholarteacher Connoisseur
My kids were born in Memphis, but mostly grew up in NC. But when my daughter had her 2nd son, she named him Memphis. Believe it or not, he really looks like a Memphis! I figure he'll either be a Nascar driver, a rodeo rider, or an evangelist! Something dynamic! What unusual names do you have in your family or circle of friends?
scholarteacher, Jun 16, 2009
yarnwoman Cohort
My son's name is Axel. He is named after my grandfather, not Axl Rose or Axel Foley.
yarnwoman, Jun 16, 2009
TennisPlayer Cohort
Someone told me about a girl who was named L-ah. Can you figure out how to say it?
TennisPlayer, Jun 16, 2009
Pisces_Fish Fanatic
Is Levi considered unusual? I love that name.
Pisces_Fish, Jun 16, 2009
lnm130 Companion
TennisPlayer said: ↑
Is it pronounced like Ella?
lnm130, Jun 16, 2009
lnm130 said: ↑
Oh that's a really good guess but no. I'll let more people guess before I reveal the answer.
tb71 Cohort
I'm guessing...L-ah pronounce...Lei?
Our two daughters are at both ends of the spectrum...Emily one of the most common and Lainie which I run across very rarely.
tb71, Jun 16, 2009
I pronounce L-ah like it sounds La-ah?
I don't have any unusual names, but I have a friend who named her daughter Emma'Leigh (Emily).
smalltowngal, Jun 16, 2009
Peachyness Virtuoso
It's something like Ldashah.
My name is weird and so is my brothers. I asked my mom why in the world couldn't she have given us normal names. I never really did get a good response. I should go by my middle name which is Inge.
Peachyness, Jun 16, 2009
kimrandy1 Enthusiast
L-dash-a.
I actually had a kid named something similar, many years ago. Her name was K-n. Ka-dash-en.
kimrandy1, Jun 16, 2009
Crzy_ArtTeacher Comrade
I'm saying it's pronounced...
Leydasha
We had this EXACT situation at our school. They intend for the - to literally come across as DASH.
Crzy_ArtTeacher, Jun 16, 2009
I think that most of the "a friend of mine knows this person whose name is..." stories are completely made up. I mean really, how many Oranjellos and Lemonjellos can there possibly be?
I really like names that are uncommon but not made up. Old-fashioned names are really cool. I especially like boy Jewish names, like Ari.
My name isn't all that common, but most people recognize it as a real name. I love my name! The only problem I have is that people either think that I'm saying my name is Cathy (I do not have a speech problem, so I don't know why they hear "Cathy"....) or they call me Casey. Ugh.
Caesar753, Jun 16, 2009
I used to think that about the Lemonjellos, too. Then we had one at my school. I think that maybe someone made them up years ago - and then people heard the name and liked it? I don't know. We haven't had our Lemonjello for years, I'd bet he's out of high school now. His middle name was James and he decided to go by L.J.
I didn't have any really unusual names this year. One year, I had a whole bunch of very old-fashioned names. Not weird, just not mainstream. Like Isaac, Ezra, Bernadette, Brenda, Linda, Jonas, Jasper, etc. I actually liked them alot.
My own kids are very mainstream and very feminine names. And they are all spelled the traditional way.
Peachyness said: ↑
Yeah maybe it was from someone on here that shared that! It's "Le dash ah". I remember sharing it over Christmas break with family so forgot who said it first!
sumnerfan Comrade
my grandfather's middle name was Uno. I kinda like it. My daughter is McClain- and it's not a family name just a recurring name in my life (last name of someone significant, street name where someone important to me lived, etc.).
sumnerfan, Jun 16, 2009
In addition to Memphis, my other grandson's middle name is Tyler (like Texas), and the granddaughters are Brooklyn and Avery, whose middle name is Cheyenne. I told my daughter she didn't look at baby name books, just atlases and road maps!
txmomteacher2 Enthusiast
My husband's middle name is Day. His mom wanted a girl to name her Doris Day, but he was born so she gave him his middle name.
txmomteacher2, Jun 16, 2009
Teacher Chele Habitué
Ok, the "dash" thing is definitely different!!!
I once taught a child named Precious.
My neice went to school with twins named Lemon Jello(pronounced Le Mon Gel-O) and Orange Jello(pronounced O Ron Gel-O. (Yep they were named after Jello flavors. Their mom spoke no English and had only been in the States for a few weeks when she named them. )
Teacher Chele, Jun 16, 2009
Sheila Comrade
My son has a very German name and I hardly see or hear of someone with the same name. However, we were in Petsmart today and our cashier had his same named spelled the same way. It made my son's day and the cashier felt happy too.
Sheila, Jun 16, 2009
giraffe326 Virtuoso
I have an unusual name. Not strange- just not common.
As for students, I have not had any strange names yet. Odd spellings (Emmalee), but nothing super unusual.
I personally tend to favor boy names for girls. Not sure why- I want to name my first born (which better be a girl Rhyann. I also like Jordan for a girl.
giraffe326, Jun 16, 2009
etcetera83 Cohort
sumnerfan said: ↑
I like your daughter's name a lot!
etcetera83, Jun 16, 2009
scholarteacher said: ↑
That's funny - My husband and I tend to lean toward places too. If we ever do have kids we have a boy and girl name picked:
Savannah Delane
Memphis Gray
Mr D Comrade
Pisces_Fish said: ↑
I had a student named Levi once, but he's the only Levi I've ever known, so I would say it's unusual. :lol:
Mr D, Jun 16, 2009
WannaTeach Companion
There is a student at my husband's school whose name is spelled a lot like this one. Her name is L-eah. It is pronounced La dash ia. No kidding. And if you don't know how to pronounce, she becomes upset.
WannaTeach, Jun 16, 2009
sevenplus Connoisseur
I appreciate how this thread was started asking for family or friend names, NOT student names. I certainly think it should remain that way.
My son's name is Rui.
Other names on this thread that I love and were actually on my list before he or his brother were born are Levi and Ari.
sevenplus, Jun 16, 2009
Seven+ - how do you pronounce your son's name? Is it Roo-e?
A favorite name of mine is Channing. It is my grandmother's maiden name. If I had another child, Channing it would be--boy or girl.
Another is Nash. Oh, my mother's middle name (she may not speak to me after I tell) is Undine. I have only seen this name once in a book I read. Certainly unique.
etcetera83 said: ↑
It sounds like "Rudy" without the d. When people mis-hear it, they hear it as "Rudy."
I think we can talk about names in general (students', our childrens', friends', etc.) as long as it doesn't become judgemental. I've been impressed so far at how not one poster has said, "that's WEIRD" or "how could they do that to the kid?" or whatever. There is a big difference between saying that someone has an unusual name and a bad one...and sometimes, those moms who named their kids unusual names do it on purpose! They want their kids to stand out, and they think common names are boring. Sometimes.
I think it's important to note that what is considered unusual in one part of the country may be completely common in other parts of the country!
sevenplus said: ↑
Does your son's name have a story behind it, or a meaning? I'd love to hear!
kim~I was going to ask seven the same thing. It's so unique. I love it!!
I tutored a Levi this year, and dh and I considered naming our son (if we ever had one) Levi.
Rui means "prince" in Portugese, or so I'm told. A Portugese soccer player has that name (it's much more common in Portugal than here, obviously) and that's how my husband came across it. He follows international soccer.
It is pronounced differently in Portugese, but I don't know how to type that phonetically!
Funny story: when he was born my husband called my mom right away and then she called the rest of the family. My brother called me and said, "Mom told me his name, but I don't think she got it right." When I asked him what she said, he pronounced it perfectly. :haha: I don't think he's much of a fan of unique names. Oh well. We gave him a very common and traditional middle name. If he grows up hating his unique name, he can always go by his middle. But it really suits him. He's 3 and the other day he asked, "What are the other Ruis in the world doing right now?" :lol:
Years ago I worked with a female professor whose name was Rue.
Pronounced the same as your son just for a girl. She was a a great person. I loved working with her.
glen Companion
My sons have traditional, Old Testament/Saint names. Neither is odd, but neither is over-popular. With a definite common Irish last name (beginning with an O'), we had to try to find something that there wouldn't be so many of, like Sean O' or Patrick O'.
glen, Jun 16, 2009
Thanks, me too. My name is very common and I really wanted her to have one that if she heard someone call it across a crowded room she would know they were talking to her. The only down side is some people think it's a masculine name and assume she's a boy (like a basketball signups.)
My nephew's name is Ryken. He's six months old. When my sister-in-law first told me that Ryken would be his name, I really didn't care for it. But now that he's here, I couldn't imagine him being anything else!
chebrutta Enthusiast
My name isn't uncommon (actually growing in trend)... but no one seems to be able to say it or spell it. If I say it over the phone, I'm either called "Martha" or "Marcia." Grr.
A friend has a baby girl named Paislyn; another has Neela; another has Aoife.
chebrutta, Jun 16, 2009
Jem Aficionado
I want my child/ren to have unusual names. If we have a girl, she'll be Elsa. That was my husband's favorite aunt's name. There are a lot of Ellas, Ellies, Lily's, etc. around here, so I hope it doesn't get lost in those. If we have a boy, I'm leaning towards Samson or Theodore (Teddy for short).
Dh's middle name is Knoll, and I think we'll keep that for our child's middle name. My brother's middle name is Wade, and I love that as well. Both were maiden names in our families.
Jem, Jun 16, 2009
MichaeldRind,
TeacherNY,


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Designed and Developed for INVOKING THE GODDESS - Website for the Devotion to Kannaki-Pattini is an inspiring example of Hindu-Buddhist syncretism in Sri Lanka.
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I was given the opportunity to do a shoot for "Trendrally" online shopping portal that brings designers and their unique masterpieces directly to the customers.
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I happened to enjoy some workshop freebies for the recently purchased running shoes when a local store gave out some free coupons to some art workshop for kids. And, since my own son is out of town for a long vacation, I awarded the art coupons to my own nephew who enjoyed art than most people at home.
Summer is an ideal time to learn new skills as kids have at least 6 weeks to enjoy the school break. It is then unsurprising that local institutions initiate training and workshops for kids. These include some sports clinic like basketball, soccer or swimming to name a few and art training is not at all excluded from the list.
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Home / Early Childhood Assessment Instruments
Early Childhood Assessment Instruments
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text:
\section{Introduction}
Semiconductor quantum dots (QDs) exhibit a variety of confinement-related optical and electronic properties useful for opto-electronic device applications such as QD lasers and detectors. In particular, broad efforts are currently underway to develop new techniques for controlling spin degrees of freedom in QDs for quantum information processing. A key quantity for the spin manipulation is a g-factor, which is a coefficient connecting magnetic dipole moments with the spin degrees of freedom.
Therefore, the knowledge of electron and hole g-factors and their control are important.
For example, zero electron g-factor is required to convert the photon qubit into the electron spin qubit~\cite{{Kosaka01}} while the system with a large g-factor is preferable
for controlling spin qubit in terms of the energy selectivity.
The g-factors of self-assembled QDs have been obtained by optical measurements and transport measurements. Generally, the electron g-factor is deduced from transport measurements
while the exciton g-factor, which is the sum of an electron and a hole g-factors, is deduced from optical measurements. In the optical measurements, since the photoluminescence (PL) is generated by the annihilation of an electron and a hole, it is usually difficult to independently obtain an electron or a hole g-factor of QDs. In addition, sensitivity of the g-factors to the spatial confinement has been predicted by theoretical studies and partly confirmed in the experiments~\cite{Nakaoka04}.
The obtained values of the g-factors are much different from bulk ones possibly due to size quantization, strain, and other effects, however those effects are difficult to evaluate nondestructively and noncontactly for individual QD. Therefore, the direct probing method of the electron or hole g-factor is required for individual QD target.

In this study, we demonstrate the precise measurements of electron and hole g-factors in single InAlAs QDs by using the optically induced nuclear field. The measurement principle is based on the fact that nuclear field is effective only on electrons and can compensate the external magnetic field.
We first show that the nuclear field exactly cancels the external magnetic field  at one edge of nuclear bistability.  Recently, we proposed to use the cancellation of external and nuclear field for photon-spin qubit conversion to dispense with the zero g-factor engineering~\cite{Muto05}. The cancellation at the bistability indicates that the condition for the qubit conversion is automatically realized there.
Then, the measured Zeeman splitting corresponds to that of not an exciton but a hole, and therefore the hole g-factor is obtained precisely. In order to raise the precision of the obtained value, we measured the hole g-factor at some different excitation powers. Together with the exciton g-factor that is evaluated by the linearly polarized excitation, the electron g-factor is obtained.

We use the self-assembled In$_{0.75}$Al$_{0.25}$As/Al$_{0.3}$Ga$_{0.7}$As QDs which were grown by molecular beam epitaxy on a (100) GaAs substrate~\cite{Sasakura04}.
Single QDs are studied by using a standard micro-PL ($\mu$-PL) setup with a microscope objective lens.
To limit the observable QD number, small mesa structure with a typical top lateral diameter of $\sim$150 nm was fabricated~\cite{Yokoi05}. The $\mu$-PL measurements were performed at 5 K under the magnetic field $B_{\rm z}$ up to 5 T in Faraday geometry. For excitation, cw Ti:sapphire laser was employed.
The excitation light polarization was controlled precisely by the polarization selective optics and  waveplates. The $\mu$-PL from QDs was collected by the same microscope objective and was dispersed by a triple-grating spectrometer, and was detected with a liquid-nitrogen cooled Si-CCD camera.
The system resolution was $\sim$12 $\mu$eV and the spectral resolution that determines the resonant peak energies was found to be less than 5 $\mu$eV by the spectral fitting. The typical exposure time of the CCD camera was 1 sec. to obtain one spectrum with a high signal-to-noise ratio.

\begin{figure}[t]
  \begin{center}
    \includegraphics[width=240pt]{Fig1.eps}
\caption{Graphical representation of the dependence of OHS on $B_{\rm z}$ for $\sigma^-$ excitation. (a) The steady-state $\langle {I_{\rm z} } \rangle$ of Eq.~\ref{eq1} is determined by the balance between the Lorentzian-shaped polarization term and the depolarization term (a straight line). The thick curves represent the polarization terms at the low and high critical $B_{\rm z}$ ($B_{\rm N}^{\rm LC}$ and $B_{\rm N}^{\rm HC}$) for the bistable behavior. (b) The resultant OHS shows the bistable response on $B_{\rm z}$. The curves for different excitation powers are also depicted. The curve with a larger excitation power has the larger $B_{\rm N}^{\rm HC}$. Note that the top of the curves is always on the line of $|g_{\rm z}^{\rm e}| \mu_{\rm B} B_{\rm z}$ (a dotted line).} \label{Fig1}
    \end{center}
\end{figure}
Since the g-factor measurement in this study is based on the cancellation of $B_{\rm z}$ for an electron in a target QD by the optically induced nuclear field $B_{\rm N}$, we begin with the explanation of the response of $B_{\rm N}$ on $B_{\rm z}$.
Figure~\ref{Fig1}(a) shows the $B_{\rm z}$-dependence of a nuclear spin polarization term (Lorentzian-shaped function) and depolarization term (straight line) of the following rate equation that represents the nuclear spin dynamics~\cite{Abragam61,OptOrientation};
\begin{equation}
\frac{{d\left\langle {I_{\rm z} } \right\rangle }}{{dt}} = \frac{1}{{T_{\rm{NF}} }}\left[ Q \left( {\left\langle {S_{\rm z} } \right\rangle  - S_{0} } \right)-{\left\langle {I_{\rm z} } \right\rangle} \right] - \frac{1}{{T_{\rm{ND}} }}\left\langle {I_{\rm z} } \right\rangle, \label{eq1}
\end{equation}
where $\langle {I_{\rm z} } \rangle$ and $\langle {S_{\rm z} } \rangle$ are the averaged nuclear and electron spin polarizations, $S_{0}$ is the thermal electron spin polarization, $1/T_{\rm{NF}}$ and $1/T_{\rm{ND}}$ are the nuclear spin polarization and depolarization rates, and
$Q \ (=\left[{I\left( {I + 1} \right)}\right]/\left[{S(S + 1)}\right])$ is a momentum conversion coefficient from electron spin to nuclear spin system in the spin flip-flop process.
Based on the general form of the spin-flip process in the precessional decoherence type~\cite{OptOrientation}, the spin transfer rate $1/T_{\rm{NF}}$ is given as follows by assuming the uniform electron wavefunction in a QD~\cite{Braun06,Tartakovskii07,Maletinsky07};
\begin{equation}
\frac{1}{T_{\rm{NF}} }= \left[\frac{n_{\rm e} \tau_{\rm c}^2}{\tau_{\rm R}} \left(\frac{A }{N \hbar} \right)^2\right] \bigg/ \left[1+ \left(\frac{\tau_{\rm c}}{\hbar} \right)^2 \left\{g_{\rm z}^{\rm e} \mu_{\rm B} (B_{\rm z} \pm B_{\rm N}) \right\}^2 \right],
\label{eq2}
\end{equation}
where $A$, $N$, $n_{\rm e}$, and $\tau_{\rm R}$ are the hyperfine coupling constant, number of nuclei, electron density in the QD, and lifetime of an electron, respectively. $\tau_{\rm c}$ is the correlation time of the coupled electron-nuclei system with the broadening $\hbar/\tau_{\rm c}$. The magnitude of $B_{\rm N}$ is related to the steady state $\left\langle I_{\rm z} \right\rangle$ as $B_{\rm N}=A \left\langle I_{\rm z} \right\rangle / |g_{\rm z}^{\rm e}| \mu_{\rm B}$ and the direction can be selected to parallel or anti-parallel to $B_{\rm z}$ by the choice of the helicity of circular excitation.
According to Eq.~\ref{eq2}, the compensation of $B_{\rm z}$ by $B_{\rm N}$ reduces the electron Zeeman splitting i.e. $g_{\rm z}^{\rm e} \mu_{\rm B} (B_{\rm z} - B_{\rm N})$ and results in the increase of  $1/T_{\rm{NF}}$.
From this simple model, the coupled electron-nuclear spin system shows a static hysteresis loop in the relation between the Overhauser shift (OHS=$A\langle I_{\rm z} \rangle$) and three variable parameters: $n_{\rm e}$ ($\propto$ excitation power), $\langle {S_{\rm z} } \rangle$($\propto$ excitation polarization) and $B_{\rm z}$.
By some groups and us, the hysteretic behavior of OHS in QDs are recently observed on the excitation power~\cite{Braun06,Tartakovskii07,Kaji07}, on the excitation polarization~\cite{Kaji07}, and on $B_{\rm z}$~\cite{Maletinsky07}.

\begin{figure}[t]
  \begin{center}
    \includegraphics[width=240pt]{Fig2.eps}
  \end{center}
  \caption{(a) PL spectra of a single QD at 0 T (5 K). (b) Contour plot of the Zeeman-split PL lines of $X^+$ for $\sigma^-$-excitation as a function of $B_{\rm z}$ (upper panel). The $B_{\rm z}$-dependence of Zeeman splitting energy (middle panel). The $B_{\rm z}$-dependence of OHS (bottom panel). The abrupt decrease of the splitting energy at $\sim$4.3 T is observed clearly in all figures. (c) The observed Zeeman splitting energies of hole (squares), electron (triangles), and exciton (circles) are plotted as a function of $B_{\rm z}$. Inset shows the transitions of $X^+$ PL.}
  \label{Fig2}
\end{figure}
The steady state $\langle {I_{\rm z}} \rangle$ of Eq.~\ref{eq1} are expressed graphically by the intersecting points of both polarization and depolarization terms, as shown in Fig.~\ref{Fig1}(a), and the trajectory of the steady state $\langle {I_{\rm z} } \rangle$ is depicted as a function of $B_{\rm z}$ in Fig.~\ref{Fig1}(b). Both figures are depicted for $B_{\rm N}$ antiparallel to $B_{\rm z}$, which is realized by $\sigma_-$ excitation for InAlAs QDs.
The Lorentzian shaped polarization term moves right with increasing $B_{\rm z}$.
At the low $B_{\rm z}$, the intersection is unique (e.g. point $a$) and then follows the straight line of the depolarization term with \textit{increasing} $B_{\rm z}$. Beyond the lower critical magnetic field $B_{\rm z}^{\rm LC}$, two new solutions (e.g. $g$ and $i$) appear, but the system still remains in the high $\langle {I_{\rm z}} \rangle$ state. Just beyond the higher critical magnetic field $B_{\rm z}^{\rm HC}$, this high $\langle {I_{\rm z}} \rangle$ state (point $e$) disappears and the $\langle {I_{\rm z}} \rangle$ jumps down to the low $\langle {I_{\rm z} } \rangle$ state (point $f$). For further increase in $B_{\rm z}$, the state stays on the lower branch.
In the case of decreasing $B_{\rm z}$, the state on the lower branch remains at $B_{\rm z}^{\rm LC}$ where the low $\langle {I_{\rm z}} \rangle$ state $h$ disappears and the system has to return to the upper branch (point $c$). In the region between $B_{\rm z}^{\rm LC}$ and $B_{\rm z}^{\rm HC}$, there are two stable states (e.g. $d$ and $g$) and which one of them is realized depends on the history, i.e. on whether one comes from larger or smaller $B_{\rm z}$. The intermediate branch is unstable (e.g. point $i$).
Such bistable and hysteretic behaviors of OHS on $B_{\rm z}$ were clearly observed in the low range of $B_{\rm z}$ ($\le$2 T) in single In(Ga)As QDs by Maletinsky et al~\cite{Maletinsky07}.
Note that the following two points in this nonlinear behavior; \\
1. Perfect cancellation of $B_{\rm z}$ by $B_{\rm N}$ is achieved at $B_{\rm z}^{\rm HC}$ since the OHS at the time is the same as the electron Zeeman splitting $|g_{\rm z}^{\rm e}|\mu_{\rm B} B_{\rm z}$ (see the dotted line in Fig.~\ref{Fig1}(b)). \\
2. Non-zero OHS is predicted at $B_{\rm z}$=0. (This was observed experimentally~\cite{Eble06,Lai06}.)\\
From the above explanation, the hole g-factor $g_{\rm z}^{\rm h}$ can be obtained from the Zeeman splitting at $B_{\rm z}^{\rm HC}$, where $B_{\rm z} - B_{\rm N}=0$ is achieved and the electron Zeeman splitting is zero exactly.

PL spectra of a target single InAlAs QD at 0 T is shown in Fig.~\ref{Fig2} (a). The spectra was obtained at the wetting layer (WL) excitation ($\sim$730 nm) by the depolarized light. The excitation gives rise to the transition between the WLs in conduction and valence bands.
The figure shows almost all emission lines from an isolated QD for the WL excitation with the moderate power.
Through various measurements for assignments of PL spectra~\cite{Kumano06}, we conclude that the PL lines in the figure originate from the same single QD and can be attributed to $X^{+}_{T}$ (triplet state of positively charged exciton), $XX^{0}$ (neutral biexciton), $XX^{+}$ (positively charged biexciton), $X^{0}$ (neutral exciton), and $X^{+}$ (singlet state of positively charged exciton) from the low energy side.
Hereafter, we focus on the $X^{+}$ PL because the PL is strongest in the case of WL excitation and $X^+$ PL has no fine structure due to no exchange interaction.

Figure~\ref{Fig2}(b) shows a typical nonlinear behavior of the steady state $\langle {I_{\rm z}} \rangle$ around $B_{\rm z}^{\rm HC}$ for $\sigma_-$-excitation with a fixed excitation power; the contour plot of the Zeeman-split PL intensity (upper panel), Zeeman splitting energy (middle panel), and OHS (bottom panel) in the $B_{\rm z}$ range of $4-5$ T. In the upper panel, the high (low) energy line is $\sigma_-$($\sigma_+$)-polarized PL and the separation corresponds to the Zeeman splitting affected by $B_{\rm N}$, i.e. $g_{\rm z}^{\rm h} \mu_{\rm B} B_{\rm z}+g_{\rm z}^{\rm e} \mu_{\rm B} (B_{\rm z}-B_{\rm N} )$. Remember that $B_{\rm N}$ is effective only for electrons.

As shown in Fig~\ref{Fig1}(b), before the abrupt change the $B_{\rm N}$ overcompensates $B_{\rm z}$, i.e. $B_{\rm z}-B_{\rm N} < 0$. Increasing $B_{\rm z}$ under a constant excitation power, $B_{\rm z}-B_{\rm N}=0$ is achieved and then abrupt change of the Zeeman splitting occurs at $B_{\rm z}^{\rm HC}$=4.3091 T according to the aforementioned bistable nature.
At this $B_{\rm z}$, the electron Zeeman splitting is zero and only the hole Zeeman splitting remains.
Then, from the Zeeman splitting, we can directly deduce the hole g-factor $g_{\rm z}^{\rm h}$. Note that the slopes of the Zeeman splitting, i.e. g-factors, before and after the abrupt decrease are clearly different due to the cancellation of the electron Zeeman splitting.
From the bottom panel, the OHS decrease from $\sim$90 $\mu$eV to $\sim$30 $\mu$eV at $B_{\rm z}^{\rm HC}$. This decrease of OHS just corresponds to the drop from the point $e$ to the point $f$ in Fig.~\ref{Fig1}(b).

The full width $2 \hbar/\tau_{\rm c}$ of the Lorentzian polarization term is estimated to be $\sim$30 $\mu$ eV since the coherence time was measured to be $\sim$45 ps in the temporal domain by the single-photon Fourier spectroscopy and in the spectral domain for this QD under the WL excitation~\cite{Adachi07}. Therefore, the point $e$ in Fig.~\ref{Fig1}(b) is very closely located on the peak of the narrow Lorentzian polarization term together with a long depolarization time (several ms) and the difference between $B_{\rm z}^{\rm HC}$ and $B_{\rm N}$ is negligible.
After the abrupt decrease, the Zeeman splitting and OHS show the small fluctuation, which implies the existence of the excitation power fluctuation.
Since $B_{\rm z}^{\rm HC}$ is a function of the excitation power as shown in Fig.~\ref{Fig1}(b),
if the power fluctuates positively, the corresponding changes of the OHS and Zeeman splitting are found  after the abrupt decrease.
Therefore, by systematically changing the excitation power, we can observe the the abrupt change at different $B_{\rm z}^{\rm HC}$ in order to raise the precision of the deduced g-factors. The obtained values of the hole Zeeman splitting energy are plotted (squares) as a function of $B_{\rm z}^{\rm HC}$ in Fig.~\ref{Fig2}(c). We measured also the Zeeman splitting energies of $X^+$ PLs at the linearly polarized excitation (circles), which represents the difference of the transition energies as shown in the inset. From both data, we deduce the electron Zeeman splitting energy as a function of $B_{\rm z}$. Consequently, $g_{\rm z}^{\rm h}$ and  $g_{\rm z}^{\rm e}$ are evaluated as $+2.54 \pm 0.01$ and $-0.37 \pm 0.02$, respectively, by linear fitting. An electron g-factor in InAlAs QDs has the opposite sign of that in In(Ga)As QDs\cite{Bayer01,Bayer02}. The method used here is very powerful to obtain not only the magnitude but also the sign of electron and hole g-factors in a target single QD. This work provides valuable information on InAlAs/AlGaAs QDs which have been reported so far by only a few studies about the exciton g-factor~\cite{Hinzer01}.

In summary, we proposed the method of individual evaluation of electron and hole g-factors of single InAlAs quantum dots by using the optically induced nuclear field. The cancellation of $B_{\rm z}$ by $B_{\rm N}$ for the electron Zeeman splitting gives the precise value of the hole g-factor.
By combining it with the Zeeman splitting for linearly polarized excitation, the magnitude and sign of the electron and hole g-factors in the growth direction are obtained. The measurements by using the nuclear field gives not only a distinctive technique to obtain the g-factors but also an important milestone for qubit conversion.

The authors would like to acknowledge Y. Toda for fruitful discussions.
This work was financially supported by a Grant-in-Aid for Scientific Research from the Ministry of Education, Culture, Sports, Science, Japan.

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