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CLIMATE CHANGE, DISASTER RISK, AND THE URBAN POOR
TABLE A6.7 Distribution of Vulnerable Groups Located in High-Risk Zones Event
PSUs1
%
Population
%
Housing
%
I. Extreme precipitation II. Slopes over 15 degrees III. Heat waves I + II I + III II + III I + II + III Vulnerable in high-risk zones Total vulnerable
48 288 117 59 1 23 0 536 1354
3.55 21.27 8.64 4.36 0.07 1.70 0.00 39.59 100
179,019 1,004,586 367,450 251,118 39 62,449 0 1,864,661 4,635,298
3.86 21.67 7.93 5.42 0.00 1.35 0.00 40.23 100
38,909 208,546 76,771 53,455 10 13,175 0 390,866 964,144
4.06 21.63 7.96 5.54 0 1.37 0.00 40.54 100
Source: Leon et al. (2010). 1
PSU refer to primary sampling units defined in the context of the 2000 census.
Economic Costs of Climate Change—Another important aspect of the socioeconomic assessment was the analysis of the economic costs of climate change in terms of GDP for the Federal District. This analysis incorporated four scenarios. The base scenario, named A2, does not include climate change impacts and assumes 1.99 percent of annual GDP growth, 1.81 percent of annual GDP per capita growth, and 18 percent of population growth for 2100. The other three scenarios correspond to different goals on reduction of greenhouse gas emissions considered in international negotiations (that is, 550, 450, and 350 parts per million, or ppm). The analysis incorporated three discount rates (0 percent, 1 percent, and 4 percent); however, based on the literature on the costs of climate change, the authors recommend using 0 percent to draw conclusions. Table A6.8 shows costs for each scenario in terms of GDP reduction and additional number of poor people by 2100 for the Federal District, using a 0 percent discount rate. Shown is the average value, as well as the 95 percent confidence interval in parentheses. Under the status quo scenario (A2), it is expected that the GDP will be reduced 19 times on average. These results are not too different from those under the 550 ppm scenario. However, if the 350 ppm scenario is realized, the benefits could reach 32 times the current GDP (in terms of avoided losses). Also under the A2 scenario, the number of poor is projected to increase to over 1 million (or about 10 percent of population in 2100), although the average increase is expected to be 450,000. The analysis also pointed out that economic losses are not distributed equally among administrative units. Those that will lose the most are those that are currently worse off. In other terms, if the temperature increases by 2°C, Mexico City could lose up to 7 percent of its GDP and get 150,000 additional poor annually.