From the Editor

Climate change discourse has gone through a "sea level change" sometime recently. Where only a decade ago assertions by climate model-toting arcane scientists were lashed at by dug-in and/or graying contrarians, we now receive a growing flow of scientific observations related to current and geologically ancient climate variations. What it all means in terms of pending climate change is still hardly certain, but the word "likely" is feeling more appropriate. And while we are measuring current change, a whole "new" science of ancient climate measurement is evolving.

Let's check the box score. It is a fact that atmospheric carbon dioxide has increased by 30 percent since the beginning of the industrial revolution.

It is a widely accepted theory that increased atmospheric carbon dioxide will lead to global warming.

There is growing evidence that global climate is warming, as supported by significant loss of polar ice volume, sea level rise, 1997 and 1998 being the hottest years on record, and the 20th century being the warmest in the past 1,200 years.
It is predicted that, with current emission trends, atmospheric carbon dioxide concentrations will at least double during the 21st century and Earth's average temperature will rise another 1 to 3.5 degrees Celsius. It is also predicted that Earth's response to global warming will exceed local expectations in terms of the rates and magnitudes of changes for example, extensive flooding in coastal areas where 50 to 70 percent of Earth's population lives.

It is assumed that even if we stopped emissions now, the impacts of cumulative emissions would likely persist.
And finally, the predicted global warming cannot now be stopped. I don't know about you, but this leaves me feeling like the paraphrasing of the Second Law of Thermodynamics, namely: you can't win, you can't break even and you can't get out of the game!

The expanding field of climate change studies is a) measuring current changes; b) investigating geologically ancient changes; c) learning to predict intermediate-range changes (±100 years); and d) identifying possible social impacts of predicted intermediate-range changes. This issue of Geotimes presents a sampling of topics from these diverse fields. If you enjoy your reading, pass the issue along to friends, or order additional copies for Christmas stocking stuffers.

Matt Huber, in his article, "Global Climate Change: A glance in the rearview mirror," presents a fast-moving and informative review of climate change research from the geological record. His use of the term "proxies" as indicators of past climate properties somehow eases one's understanding of the terminology-laced vignettes. In fact, after absorbing "alkenones, boron isotopes, carbon-13, and even stomata on ginko leaves," my mind flipped spontaneously to the world and words of Harry Potter.

And speaking of proxies, our second feature by Paul Baker discusses one of the latest: lake sediments. Baker describes recent work in South America's Lake Titicaca and the climate stories those sediments tell.
Steve Stanley's essay "To Predict the Unpredictable" is our Comment this month. He raised two particular points for me: first, our narrow, first-hand experience with climate will be unbelievably enriched by climate research from the geologic column; and second, atmospheric carbon dioxide concentrations are not necessarily a reliable proxy for climate.
And in the News Note "Sea level today and tomorrow," Geotimes Associate Editor Christina Reed reports on an all-too current issue. We need to answer: What is going to happen with sea level? How much and how soon? Given the cost of preventative and remediative measures, coastal communities need short- and intermediate-term information.
It is shaping up that the earth sciences are to play a major role in understanding climate change. This is good news for earth scientists and for society.

Believe your compass,

Samuel S. Adams, Editor-in-Chief

P.S.: Although there are a multitude of information sources about climate change, the number of sources that do a good job of presenting that information and placing it in a helpful context are few and far between. My own thoughts have been informed and enriched by the Environment Canada Web site:

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