Science of climate change

摘要

A complex debate is underway on climate change linked to proposals for costly211u001emeasures that would reshape our power grid. This confronts technical experts 211u001eoutside of the geophysical disciplines with extensive, but unfamiliar, data both 211u001esupporting and refuting claims that serious action is warranted. For example, 211u001eevidence is brought to the table from one group of astrophysicists concerned with 211u001esunspots--this group believes there is no issue man can manage; while another 211u001egroup of oceanographers concerned with the heat balance in the world's oceans are 211u001every alarmed at the loss of arctic ice. What is the evidence. In an effort to put 211u001esome of these issues in perspective for a technical audience, without a 211u001ebackground in geophysics, a brief survey will consider (1) an overview of the 300 211u001eyears of scientific inquiry on man's relationship to climate; (2) a basic 211u001ediscussion of what is meant by the 'greenhouse' and why there are concerns which 211u001einclude not only CO(sub 2), but also CH(sub 4), N(sub 2)O, and CFC's; (3) the 211u001egeological record on CO(sub 2)--which likely was present at 1,000 times current 211u001elevels when life began; (4) the solar luminosity and sunspot question; and (5) 211u001ethe current evidence for global climate change. We are at a juncture where we are 211u001eattempting to understand the earth as an integrated dynamic system, rather than a 211u001ecollection of isolated components.