Karina

“The National Academy of Sciences undertook its first major study of global warming in 1979. At that point, climate modeling was still in its infancy, and only a few groups, one led by Syukuro Manabe at the National Oceanic and Atmospheric Administration and another by James Hansen at NASA’s Goddard Institute for Space Studies, had considered in any detail the effects of adding carbon dioxide to the atmosphere. Still, the results of their work were alarming enough that President Jimmy Carter called on the academy to investigate. A nine-member panel was appointed. It was led by the distinguished meteorologist Jule Charney, of MIT, who, in the 1940s, had been the first meteorologist to demonstrate that numerical weather forecasting was feasible. The Ad Hoc Study Group on Carbon Dioxide and Climate, or the Charney panel, as it became known, met for five days at the National Academy of Sciences’ summer study center, in Woods Hole, Massachusetts. Its conclusions were unequivocal. Panel members had looked for flaws in the modelers’work but had been unable to find any. “If carbon dioxide continues to increase, the study group finds no reason to doubt that climate changes will result and no reason to believe that these changes will be negligible,”
― Elizabeth Kolbert, Field Notes from a Catastrophe

“Adding carbon dioxide, or any other greenhouse gas, to the atmosphere by, say, burning fossil fuels or leveling forests is, in the language of climate science, an anthropogenic forcing. Since preindustrial times, the concentration of CO2 in the atmosphere has risen by roughly a third, from 280 to 378 parts per million. During the same period, the concentration of methane has more than doubled, from .78 to 1.76 parts per million. Scientists measure forcings in terms of watts per square meter, or w/m2, by which they mean that a certain number of watts have been added (or, in the case of a negative forcing, like aerosols, subtracted) for every single square meter of the earth’s surface. The size of the greenhouse forcing is estimated, at this point, to be 2.5 w/m2. A miniature Christmas light gives off about four tenths of a watt of energy, mostly in the form of heat, so that, in effect (as Sophie supposedly explained to Connor), we have covered the earth with tiny bulbs, six for every square meter. These bulbs are burning twenty-four hours a day, seven days a week, year in and year out. If greenhouse gases were held constant at today’s levels, it is estimated that it would take several decades for the full impact of the forcing that is already in place to be felt. This is because raising the earth’s temperature involves not only warming the air and the surface of the land but also melting sea ice, liquefying glaciers, and, most significant, heating the oceans, all processes that require tremendous amounts of energy. (Imagine trying to thaw a gallon of ice cream or warm a pot of water using an Easy-Bake oven.) The delay that is built into the system is, in a certain sense, fortunate. It enables us, with the help of climate models, to foresee what is coming and therefore to prepare for it. But in another sense it is clearly disastrous, because it allows us to keep adding CO2 to the atmosphere while fobbing the impacts off on our children and grandchildren.”
― Elizabeth Kolbert, Field Notes from a Catastrophe

“The size of the greenhouse forcing is estimated, at this point, to be 2.5 w/m2. A miniature Christmas light gives off about four tenths of a watt of energy, mostly in the form of heat, so that, in effect (as Sophie supposedly explained to Connor), we have covered the earth with tiny bulbs, six for every square meter. These bulbs are burning twenty-four hours a day, seven days a week, year in and year out.”
― Elizabeth Kolbert, Field Notes from a Catastrophe

“at 378 parts per million, current CO2 levels are unprecedented in recent geological history. (The previous high, of 299 parts per million, was reached around 325,000 years ago). It is believed that the last time carbon dioxide levels were comparable to today’s was three and a half million years ago, during what is known as the mid-Pliocene warm period, and it is likely that they have not been much higher since the Eocene, some fifty million years ago. In the Eocene, crocodiles roamed Colorado and sea levels were nearly three hundred feet higher than they are today. A scientist with the National Oceanic and Atmospheric Administration (NOAA) put it to me—only half-jokingly—this way: “It’s true that we’ve had higher CO2 levels before. But, then, of course, we also had dinosaurs.”
― Elizabeth Kolbert, Field Notes from a Catastrophe