Given the growing evidence that temperatures are likely to increase 3-4C during this century, the exigency for aggressive and effective adapation responses continus to grow. For those of you teaching climate policy courses, especially at the graduate level, an excellent new piece has been published on how to assess the vulnerability of least-developed countries to climate-related extreme events, and the optimal timing of adaptation funding over the next five decades, Patt, et al., Estimating Least-Developed Countries’ Vulnerability to Climate-Related Extreme Events Over the Next 50 Years, 107 PNAS 1333-1337 (2010) (0pen access). The study employed an empirically derived model of human losses to climate-related extreme events, as an indicator of vulnerability, and sought to assess optimal allocation of adapatation funding on a 50-year timescale. The study developed a set of scanrios for losses in Mozambique and then extrapolated the results to 23 other developing countries.
Among the key findings of the study:
- Vulnerability in the countries studied may rise faster in the next two decades than in the three decades thereafter, indicating that substantial frontloading of adaptation interventions would be judicious;
- While the overall need for adaptation measures will continue to rise thereafter, LDCs will likely be capable of engaging in a larger share of autonomous adaptation by the second quarter of the century, reducing both their losses associated with climate change and need for external financial assistance;
- The two conclusions above put into question a primary rationale for slowing ramping up assistance, ie. that adaptation needs will increase as climate change continues;
- As we cross temperature thresholds of 2C, steadily rising climate impacts or the effects of cumulative changes on ecosystems may overwhelm the ability of either rich or poor countries to adapt.
The conclusions of this study, if validated in other research, could be extremely important, in that it emphasizes the urgency of accelerating adaptation commitments under the successor to the Kyoto Protocol. Among the questions that might be interesting to discuss in class are the following:
1. Does the study make a compelling argument that extreme weather events is a reliable proxy for projected climate change impacts, including cumulative impacts, e.g. sea level rise and increasingly negative impacts of temperature and precipitation declines on agricultural production? If not, how might that impact its conclusions?
2. Does the study do a good job of assessing potential ecosystem impacts, and is it conclusions about capabilities to respond valid in this context?
3. If its conclusions that temperature increases of 2C and above might overwhelm adaptation efforts, and this could occur by mid-century, is it conclusions that income in developing countries, and their ability to autonomously adapt, valid? If not, what would be the implications for adaptation interventions?