Forecasters say El Nino may be developing June 8, 2009
Computer models that forecast climate differ, the agency noted, with some predicting arrival of El Nino while others expect continued neutral conditions.
Compare that estimate to predictions from Jan 2009:
La Niña Returns, NASA Watches Sea Surface Indicators
01.26.09
La Niña conditions are likely to continue in the Northern Hemisphere during the spring of 2009. That's the forecast from the National Oceanic and Atmospheric Administration's (NOAA) Climate Prediction Center, National Center for Environmental Prediction and National Weather Service in their official statement on January 8, 2009
The inability of models to forecast EL Nino variability does not, in fact, invalidate long-term climate predictions based on the atmospheric accumulation of long-lived greenhouse gases, namely CO2, CH4 and N2O. Why not? For the same reason that climate models don't predict hurricanes. El Nino is an example of ocean weather, much as hurricanes are a case of atmospheric weather. That means chaotic instability and sensitive dependence on initial conditions play large roles in the development of the phenomenon, just as in weather forecasting.
However, predictions of more extreme weather events as warming proceeds are viewed as robust, even though climate models don't specifically forecast such events. What is going on here? Are these predictions that the models are missing, and why?
For an interesting take, see this:
Response of ENSO to global warming: A perspective from the global heat balance, Sun, D
I will review progress that has been made in understanding the role of ENSO in the global heat balance. In particular, I will highlight the research leading to the view that averaged over the decadal or longer time- scales, ENSO acts as a basin-scale heat mixer in the tropical Pacific.
Here the notion is that external forcing that increases surface-subsurface differences (for example, warming of surface waters by increased GHGs) is counteracted by ENSO activity, which mixes in that extra warmth. Thus, El Nino seems like conversion of oceanic potential energy into global kinetic energy - or, an equatorial belch that affects global climate.
In this view, the level of ENSO activity is controlled not only by tropical heating, but also by extra-tropical cooling. It suggests that we shall see an elevated level of ENSO activity in the initial stages of global warming, but a reduced level of ENSO activity (or even a permanent El Nino state) when global warming is full-blown.
The large 1997-98 El Nino may have been an example of that. By increasing temperature differentials (vertically or horizontally) in the short term, you spawn more intense weather systems. Over the long term, an entirely new, stable climate regime will set in - one radically different from what the Earth has seen in 3 million plus years. Full-blown global warming is thus the equilibration stage, when the atmosphere is no longer acting to increase ocean temperature. It's highly unlikely that anyone now alive will live to see a new stable climate, however, as the response time to a doubling of atmospheric CO2 by 2050 is at least hundreds of years, possibly exacerbated by a permafrost methane pulse.
Once CO2 levels stabilize, how long does it take the oceans and atmosphere to reach a new thermal equilibrium? Around a thousand years? with the rate of ocean mixing being the main variable. At that point, the earth would again be in radiative equilibrium.
Study: CO2 impacts could last centuries - Rising levels could lock in droughts, sea level increases, January 27, 2009
What this emphasizes is that the oceans are going to play the dominant role as global warming progresses - and a major factor is going to be the how the deep ocean interacts with the surface layer. It's far harder to measure oceanic temperature profiles than atmospheric ones, so this is a data-limited area of research in many respects.
The effects of fossil CO2 pollution are not as irreversible as species extinction, but they are certainly not reversible under short time periods, despite recent claims by Yale researchers. It is a nice idea - the 'resiliency of nature' - but it really means very little. Easter Island was also 'resilient' - the grass didn't stop growing, did it? What if the climate had also radically changed, however?
If people and nations can't even sustainably manage resources under conditions of climatic stability, they will face certain disaster as global warming and instability progresses. Nations incapable of providing their own populations with basic resources like food and fuel will likely face violent collapse under such scenarios - it's been seen before, even without drastic climate change. The nations most at risk are those that rely heavily on trade for their provisions of basic commodities, and those with highly vulnerable water supplies. In all cases, reform of agriculture away from the fossil fuel-intensive "Green Model" is particularly important.
Google News search exercise: "fuel riots" OR "food riots" time period 2000-present
See any trends?
Here's another question for thought: what role are climatic factors and resource extraction factors playing in the current global economic downturn? Are Marxist and neoclassical economists capable of taking such factors into account in their 'econometric models'?
