Key words :
Ahead of the Curve 2: States Lead on Climate Change
29 May, 2008 11:05 am
Part 1 of a 14-minute documentary on state governments' response to the growing threat of climate change.
Key words :
The Wrong Enemy
Social Media for Scientists
Obama's Top Priority: Spark a New Energy Economy
The Ph.D. dance
Electrify America: The Founders Were Right, Let's Look to France!
For state by state emissions, see:
Lobby your state and your Senator to do the right thing!
Don't forget that CO2 stays in the atmosphere for a very long time:
There is little doubt that water is a highly significant part of the weather system and that in-turn provides the climate that we have. It is known from palaeoclimate studies that our climate can vary from snowball earth, to the Eocene hothouse. So we perturb the climate at our peril, but as you probably realise, the climate is being altered, because the radiative properties of the Earth are being changed by increasing CO2 in the atmosphere. CO2 acts both as a forcing and a feedback. Water vapour acts as a feedback and increased warming means more water vapour. Excess water vapour falls out of the atmosphere as precipitation, not so with CO2. The atmospheric lifetime of CO2 is driven by many different processes and is very long. The simplest way to explain it is to refer you to the following article.
EOS Vol. 80, No. 39, September 28, 1999, p. 453.
Climate Change and Greenhouse Gases
'..,Prediction of the future persistence of anthropogenic greenhouse gases in the atmosphere is based on mathematical models that simulate future additions and removals. The greenhouse gas concentrations predicted by these models are subject to large uncertainties in the effects of both natural processes and human activities...,
..,The persistence of anthropogenic CO2 in the atmosphere cannot be estimated with such a simple model because exchange with the ocean and sediments leads to a more complex behavior. Model simulations of oceanic CO2 uptake provide response times associated with CO2 gas exchange at the ocean surface of approximately 10 years [Liss and Merlivat, 1986; Toggweiler et al., 1989] and downward mixing of surface waters on the order of decades to centuries [Maier-Reimer and Hasselmann, 1987; Sarmiento et al., 1992]. But even when these oceanic CO2 removal processes are allowed sufficient time in the models to reach their maximum capacity, they can remove only about 70 to 85% of the anthropogenic CO2 added to the atmosphere [Archer et al., 1998; Broecker and Peng, 1982; Sarmiento et al., 1992].
Additional CO2 might be removed by burial in soils or deep sea sediments through mechanisms that, although poorly understood, are generally believed to require times extending to thousands of years [Harden et al., 1992; Schlesinger, 1990; Stallard, 1998]. Removing some of the anthropogenic CO2 by this mechanism may require reactions with carbonate sediments in the deep sea that occur on timescales of thousands of years [Archer et al., 1998; Boyle, 1983; Sundquist, 1990]. On the basis of such analyses, it is now generally believed that A SUBSTANTIAL FRACTION OF THE EXCESS CO2 IN THE ATMOSPHERE WILL REMAIN IN THE ATMOSPHERE FOR DECADES TO CENTURIES, AND ABOUT 15-30% WILL REMAIN FOR THOUSANDS OF YEARS.
The additional anthropogenic greenhouse gases that have been introduced into the atmosphere increase the IR energy absorbed by the atmosphere, thereby exerting a warming influence on the lower atmosphere and the surface, and a cooling influence on the stratosphere [Peixoto and Oort, 1992; Ramanathan et al., 1985].
The radiative influence resulting from a given incremental increase in greenhouse gas concentration can be quantified and compared as the change in downward IR flux at the tropopause, a quantity known as the radiative forcing. Climate model calculations indicate that to good approximation the global warming influence of the several greenhouse gases is equal for equal forcing [Wang et al., 1991, 1992], lending support to the utility of the concept of climate forcing and response.
Of the several anthropogenic greenhouse gases, CO2 is the most important agent of potential future climate warming because of its large current greenhouse forcing, its substantial projected future forcing [Houghton et al., 1996], and its long persistence in the atmosphere (see above).
Understanding climate response to a specified forcing is one of the major challenges facing the climate research community. The equilibrium response of the nonlinear climate system depends in complex ways on various feedbacks, such as changes in water vapor concentration and cloudiness that can augment or diminish climate response from that which would occur in the absence of such feedbacks...,'
Learn about climate science from climate scientists, without politics ? visit www.realclimate.org
Climate science can be hard to understand, the guys at RC are working climatologists who do this in their spare time. They look at the science and explain it to the public. Has links to the original science.