Climate Science: Major New Discoveries

Summary of Climate Science: 2008

This annual WRI review highlights the latest major research and innovations in climate change science and technology. It presents a timely synthesis of current understanding of global warming at a critically important time for the United States and the world. The international community is negotiating a new global agreement to reduce emissions of greenhouse gases for the period post-2012, while the U.S. Congress is drafting landmark climate and energy legislation to reduce domestic emissions. Our review of select peer reviewed 2008 science and technology publications, including those from key general scientific journals and technical journals, aims to inform policymakers and legislators, the NGO community, and the media, by:

• describing the wide-ranging potential ramifications of human-induced climate change;
• documenting the impacts that are already occurring as a result of increased global temperatures, altered precipitation patterns, sea level rise, and other changes in physical and hydrological systems; and
• identifying important advances relating to technologies that could help to reduce greenhouse gas emissions in the future.

The latest science summarized below supplies further evidence confirming that anthropogenic activities are the primary cause of rising temperatures over the last century, and supports the need for rapid and substantial greenhouse gas mitigation efforts worldwide. It also confirms that adaptation measures are increasingly required today—and will be ever more important in the future—to enhance the resilience of both human and non-human populations in a changing climate.

Similar to previous WRI Climate Science reports, this review is divided into four topic sections:

• Physical Climate
• Hydrological Cycle
• Ecosystems and Ecosystem Services
• Climate Change Mitigation Technologies.

In preparing this review, WRI drew from a wide array of influential journals as well as information from organizations and climate/energy websites (listed on page 27). Articles were drawn only from 2008 publications. Each section contains short summaries of key scientific findings and their policy and research implications. This Issue Brief, in addition to WRI’s Climate Science 2007 Review, serves to outline new developments since the release of the Intergovernmental Panel on Climate Change’s Fourth Assessment Report in 2007.

Sample Findings

Physical Climate

• Sea ice loss in the Arctic could have the potential to warm ground up to 1500 km inland, threatening to trigger “rapid degradation” of permafrost (Lawrence et al., p 3).
• The rate of growth of global carbon dioxide emissions between 2000 and 2007 was four times that of the previous decade (Global Carbon Project, p. 4).
• A large majority of warming over the last century can be attributed to human activities rather than natural factors, such as solar variability (Lean and Rind, p. 7).
• If atmospheric carbon dioxide concentrations reach 700 ppm by 2100 (concentrations in 2008 were 385.57 ppm), daily maximum temperatures are projected to rise to 40°C in the U.S. Midwest and Southern Europe and exceed 50°C in Australia, India, the Middle East, and parts of Africa (Sterl et al., p. 6).

Hydrological Cycle

• From 1996 to 2006, the rate of ice mass loss on the Antarctic continent increased by 75% (Rignot et al., p. 10).
• The rate of melting and thinning of thirty glaciers across nine mountain ranges around the world doubled between 2004–2005 and 2005–2006 (World Glacier Monitoring Service, p. 13).
• Up to 60% of the hydrological changes in the Western United States are due to human activities, a trend which, if sustained, “portends…a coming crisis in water supply” (Barnett et al., p. 14).

Ecosystems and Ecosystem Services

• Changes in 28,800 plant and animal systems and 829 physical climate systems have led scientists to conclude that human-induced warming is already “having a significant impact” on natural and physical systems (Rosenzweig et al., p. 16).
• Due to climate change-induced beetle infestations, the forests of British Columbia will turn from a small net sink of carbon dioxide to a large net source by 2020, with emissions trumping those related to forest fires (Kurz et al., p. 19).
• If carbon dioxide emissions continue unabated, tropical ocean “dead zones” are likely to increase by 50% by 2100 (Oschlies et al., p. 20).

Climate Change Mitigation Technologies

• A promising method of capturing carbon dioxide directly from the air is under research and development (Keith et al., p. 26).
• A new non-toxic, inexpensive technology for storing solar energy, with potential applications for generating hydrogen power, has been discovered (Kanan and Nocera, p. 23).