Introduction:
This addition to the YPCC web site is my effort to provide a resource for those interested in climate change who do not read the scientific literature on climate change. Each month I will summarize my picks of the highlights of climate change science news. I believe it is critical to keep up with the exploding field of climate science to work toward solutions. While this effort innevitably cannot cover all the new scientific evidence coming out, I hope it will still be a useful resource. I welcome feedback.
Background
Three decades of intensive scientific study, hundreds of peer-reviewed journal articles, countless studies, scores of devoted scientists, and untold hours of work have been expended quantifying and understanding global climate change. The vast majority of climatologists now agree that global climate change is underway, and that human activities are the largest contributor. As scientists have learned more, the seriousness and urgency of the threat of global warming has deepened, and current impacts have been measured worldwide. Many scientists and others argue that the time for responding to “climate skeptics” is over. I agree.
It is well known that human activities have caused the more than 30% rise in atmospheric CO2 and other greenhouse gases in the past few centuries, and that this rise is the largest contributor to the climate warming over the past century. There is still debate about the amount and speed that the temperature will rise in the future, due to the complexity of understanding and modeling all the elements that affect climate, but it in no way undermines the validity of the general conclusions.
Those of us working on climate change need to understand current science and be able to communicate about the essential elements of scientific knowledge on climate change. The difficulty is that climate researchers are constantly expanding and refining their understanding of human impacts on global climate.
Climate Science News Highlights - November, 2006
How fast are the ice sheets melting?
Scientists have been discussing and measuring ice sheet melting, particularly at the poles, in recent years. It has far-reaching implications for polar species, and global implications for large and rapid sea level rise. Greenland contains about 10% of global ice mass, and complete melting would raise global sea level by about 6.5 meters. Several recent studies have suggested that Greenland ice melting has accelerated dramatically since 2003. In November, in a study using new analysis techniques, Lutchke et al. confirmed that Greenland ice is melting at an accelerating rate, but suggested the rate may not be as fast as recently suggested in a September paper by Chen et al.. Cazenave (Perspective) discusses some of the reasons for the discrepancies, and calls for more research to improve estimates of ice loss in Greenland and Antarctica.
The take home message is that global warming is melting polar ice sheets, and Greenland ice is now melting at an alarming rate. Remote-sensing data and models have been employed in different ways in each of the studies, resulting in differing results. The Lutchke team found that the Greenland ice sheet has lost about 100 gigatons of ice per year between 2003 and 2005, as compared to the average ice loss rate of about 12 Gt of ice per year for the decade between 1992 and 2002. However, this estimate is much less than other recent rate calculations, which are closer to 240 Gt of ice per year for the same period. Uncertainty remains about the speed of Greenland ice loss.
Species are moving, adapting, and dying due to global warming.
As a conservation biologist, I have been aware for some time of research measuring signals from plants, flowers and animals reacting to a warming climate. Entire ecosystems have started to shift, and biologists have been out there quietly, painstakingly documenting the changes. A second major scientific story about global climate change came out in the Annual Review of Ecology, Evolution, and Systematics in November. In her paper, “Ecological and Evolutionary Responses to Recent Climate Change,” Camille Parmesan reviews the recent scientific literature quantifying the effects of global warming on living things. She reviews 866 studies, and finds evidence that climate change has affected species worldwide, in all taxonomic groups and all ecosystems. Other studies have described specific problems faced by species, populations, or areas affected by climate change, but this is the first comprehensive analysis of the planet-wide impacts of global warming on living things.
It is hard to overstate the scope of the impacts she documents. This review describes ecological changes in phenology and distribution of plants and animals in all well-studied marine, freshwater, and terrestrial groups. These observed changes are heavily biased in the directions predicted from global warming and have been linked to local or regional climate change through correlations between climate and biological variation, field and laboratory experiments, and physiological research. The most negatively affected groups include range-restricted species, particularly polar and mountaintop species, tropical coral reef organisms, and amphibians. Impacts include changes in predator-prey and plant-insect interactions, evolutionary adaptations to warmer conditions, observed genetic shifts, and extinction of entire species.
For a pdf of the full article, go to:
http://cns.utexas.edu/communications/File/AnnRev_CCimpacts2006.pdf
Thanks to excellent media coverage based on first-rate science, a resurgent Al Gore and the impresarial genius of pr”oducer Laurie David, the U. S. public may have turned an important corner in acknowledging global warming as a real and serious threat. To see Gore’s “An Inconvenient Truth” in theaters alongside “Nacho Libre” and such is extraordinary indeed.
But if Americans take the next step and ask, “OK, what do we do now?”, we encounter five other truths, most of them also inconvenient. But they do tell us what we must do and by when.
First, the United States is a quarter-century late in responding to global warming; serious climate change is already underway and requires action now, not later. There were warnings from the scientific community as early as 1979 and many in the 1980’s. We frittered away that chance to respond, and here is what we are up against now. If we want to avoid leaving a ruined world to our children, we are going to have to reduce greenhouse gas emissions by about 60 percent globally and by 80 percent in the United States and other developed countries, both by 2050. To do this, global emissions must peak by about 2020 and decline steadily thereafter. Developed-country emissions should already be declining. The United States is clearly on the wrong path. The Energy Information Administration projects that both U. S. coal use and carbon dioxide emissions are currently slated to increase by 40 percent by 2030.
Bottom line: the issue is not only real and important – it is genuinely urgent. The actions we take in the next few years will be critical.
Second, it would be comforting to think that the international community used the last two decades to build an effective international framework for climate action – comforting, but wrong. Scholars have lately been developing the concept of treaty “ossification. ” The example they cite? The climate treaty and its well-known offspring, the Kyoto Protocol. One reason is that the North-South divide has deepened in the negotiations. There has been no agreement yet on how to achieve equity in the greenhouse. Another reason, of course, is U. S. intransigence.
Bottom line: a huge effort is now required from the United States and others to revitalize international negotiations, with the aim of moving beyond the Kyoto Protocol and realizing emissions cuts such as those just mentioned. Perhaps a group of eminent international leaders outside of government should negotiate a model agreement to show that it can be done.
Third, though there are modest stirrings in Congress, we are nowhere near real action from our elected officials in Washington. Moreover, despite vigorous maneuvering by the Administration to fend off any meaningful steps to address this looming disaster, our political leaders and others in Washington are not being held accountable for failing to address a threat as serious as that of terrorism. The media still treat the climate issue primarily as a scientific, technical one.
Bottom line: it is time for this issue to become highly salient in electoral politics. Those alarmed about climate change – and that should be all of us – can start voting the issue in this year’s national elections.
Fourth, even though the public is now aware of the issue, there are only the earliest signs of a popular movement for change. The climate emergency is precisely the type of issue – long-term, complex – where far-sighted leadership from elected officials is at a premium. But we have waited long enough for that leadership, and it is time for citizens to take the helm before it is too late.
Bottom line: it is important to transform the new public awareness into a popular movement. Remember: climate change was also a Time cover story in the mid-1980’s, but no movement resulted.
Finally, the good news. The world is awash with major technological and commercial opportunities and excellent policy prescriptions to mitigate climate change – all that we need to reverse the threatening trends and prevent the direst predictions from coming to pass. And many U. S. cities, states and businesses are already showing the way. Indeed, the goal in California is precisely that noted above – an 80 percent reduction in emissions by 2050.
Bottom line: our greatest gift to the new generation can be a world sustained and whole. But only if we act now. The default option is a ruined world.
Using visual images to communicate the impacts of climate change can be extremely effective.
“The National Snow and Ice Data Center/World Data Center for Glaciology, Boulder (NSIDC/WDC) houses many photographic prints of glaciers, taken both from the air and from the ground. These photographs constitute an important historical record, as well as a data collection of interest to those studying the response of glaciers to climate change. NSIDC is partnering with the NOAA Climate Database Modernization Program (CDMP) and the National Geophysical Data Center (NGDC) to scan selected photographs and to make them available through a searchable interface.”
Go to http://nsidc.org/data/glacier_photo/index.html to find out more.
Please comment on this post and provide links to other high-impact visual resources that communicate the impacts of climate change.
