It is perhaps the supreme irony among the many ironies of 21st century human life on Earth. The World Bank, which seeks to foster economic growth everywhere on our humble little planet, has issued a dire warning about global warming in its new report Turn Down The Heat (pdf). The report was prepared for the World bank by the Potsdam Institute for Climate Impact Research and Climate Analytics. We get the take-away message from the Washington Post's World Bank warns of ‘4-degree’ threshold of global temperature increase.
The World Bank is urging stepped-up efforts to meet world carbon-reduction goals after looking at what it says would be the catastrophic consequences if average world temperatures rise more than 4 degrees Celsius (7.2 degrees Fahrenheit) by the end of the century.
In what World Bank President Jim Yong Kim acknowledged was a “doomsday scenario,” a new study by the organization cited the 4-degree increase as a threshold that would be likely to trigger widespread crop failures and malnutrition and dislocate large numbers of people from land inundated by rising seas.
The supreme irony is that it is the very economic growth the World Bank seeks to foster that is causing the planet's surface to heat up. So it is almost impossible to know what they have in mind when they issues dire warnings about the climate. One assumes it is the usual delusional mush which asserts that increases in energy efficiency and widespread adoption of clean, "renewable" forms of energy (wind, solar, etc.) will support continued economic growth as we de-carbonize the energy supply to prevent the worst climate scenarios from occurring.
Consider this graph from the report and the sample text accompanying it.
Climate change will not occur in a vacuum. Economic growth and population increases over the 21st century will likely add to human welfare and increase adaptive capacity in many, if not most, regions.
At the same time, however, there will also be increasing stresses and demands on a planetary ecosystem already approaching critical limits and boundaries. The resilience of many natural and managed ecosystems is likely to be undermined by these pressures and the projected consequences of climate change.
Economic growth and population increases will add to human welfare, but at the same time, there will be increasing stresses and demands on planetary ecosystems.
In short, we can have our cake and eat it too. 2 + 2 = 5. These statements, taken together, are contradictory. This story of the future is incoherent. This is mere babbling.
Welcome to a world of confusion. Welcome to Planet Stupid.
The projected impacts on water availability, ecosystems, agriculture, and human health could lead to large-scale displacement of populations and have adverse consequences for human security and economic and trade systems. The full scope of damages in a 4°C world has not been assessed to date...
The cumulative and interacting effects of such wide-ranging impacts, many of which are likely to be felt well before 4°C warming, are not well understood. For instance, there has not been a study published in the scientific literature on the full ecological, human, and economic consequences of a collapse of coral reef ecosystems, much less when combined with the likely concomitant loss of marine production due to rising ocean temperatures and increasing acidification, and the large-scale impacts on human settlements and infrastructure in low-lying fringe coastal zones that would result from sea-level rise of a meter or more this century and beyond.
As the scale and number of impacts grow with increasing global mean temperature, interactions between them might increasingly occur, compounding overall impact. For example, a large shock to agricultural production due to extreme temperatures across many regions, along with substantial pressure on water resources and changes in the hydrological cycle, would likely impact both human health and livelihoods. This could, in turn, cascade into effects on economic development by reducing a population's work capacity, which would then hinder growth in GDP.
Somewhere between the black line (IPCC climate scenario A1F1, also know as Business As Usual, or BAU) and the red line (scenario A1B) the Earth's surface temperature rises 4° Celsius, at which point the shit hits the fan according to the World Bank. BAU assumes global economic growth will continue at some relatively high rate until the year 2100, unimpeded by environmental or resource constraints.
The World Bank is assuming of course that the global economy will grow and grow over the course of the 21st century. They are also assuming, as everyone does, that the Earth's climate sensitivity is a 2-4.5° Celsius for a doubling of CO2 in the atmosphere to approximately 550 ppmv (parts-per-million-by-volume) with respect to pre-industrial levels, which were approximately 275 ppmv.
Where do we currently stand in 2012? We are at 391 ppmv, or 392 ppmv, depending on who you ask.
What would it take to get to 550 from 391? At an assumed linear growth rate of 3 ppmv/year, and counting anthropogenic (human-caused) emissions only, it would take 53 years to double the level of CO2 in the atmosphere with respect to the average pre-industrial level. That takes us out to the year 2065. In other words, it will take 53 years of global economic growth at something like 2.3%/year to achieve the doubling of CO2 which will result in a 4° Celsius rise in the Earth's average surface temperature.
Do you find it plausible that humankind will grow the global economy at that rate for the next 53 years? I don't. See my recent post Why Is Six Degrees Centigrade Unlikely? for an explanation of my thinking on these issues.
At this point—I can already hear you—some readers will make some uninformed, fearful predictions about non-linear, inherently unpredictable, catastrophic positive feedbacks (for example, greenhouse gas releases from thawing Arctic permafrost or methane hydrates) which will make the Earth very toasty some time in the next 50 years. That could happen, but the best science we have right now says it won't. That science says that emissions from those sources will be relatively small compared to anthropogenic emissions going forward, at least in the time frame specified.
Even another 1-1.5° Celsius rise in the Earth's average surface temperature will have dire effects on human populations and economies. Certainly we can all be extremely impressed with the "natural" events we've witnessed over the last 10 years.
As with all such studies, we must take this World Bank report with a grain of salt. Surely the notion that we can grow the global economy at something like the rate specified above (2.3%/year) for the next 53 years without causing irreversible, catastrophic damage to the Earth's environment is simply more wishful thinking for a species obsessed with growth of all kinds.