date: Tue, 31 Aug 1999 20:52:23 +0100 from: Sari Kovats subject: COP5 brochure: corrections to editorial changes in the to: parryml , Caroline_Fish , penny_bramwell , "p.martens" , "s.nijhof" , awhite , "m.cannell" , Tony Mcmichael , "R.Nicholls" , gjjenkins , "n.w.arnell" , "d.viner" , "M.hulme" , "Mtjl.jei" Dear Penny and Caroline and fellow Fast-Trackers, You may have noticed that some errors have crept into the Health Section of the Draft COP5 brochure during the editorial process. In short, in the summary and figure 3, the outcome measure is Per cent change in mortality rate and NOT absolute numbers of deaths, which would be rather a worry, as Robert has pointed out. Specific corrections are listed below. Best regards, Sari, on behalf of the health group. ><><><>><><><>><><><>><><><>><><><>><><><>><><><>><><><>><><><> In the Introduction and key findings: Current sentences on malaria are ambiguous. Need to make clear that 175 and 255 million additional people at risk is in comparison to no climate change, not unmitigation emissions. Paragraph on thermal stress is wrong for the reasons stated above. Further, the text implies that climate change will affect total mortality, whereas temperature-related mortality is only a proportion of all mortality, and therefore this statement is misleading. We suggest.. "Patterns of mortality in many large urban populations exhibit strong seasonal patterns, particularly in temperate climates, and therefore a reduction in cold winters and an increase in warm summers with climate change will cause a net decrease in temperature-related mortality in many cities. This benefit is not as great under the emission scenarios leading to CO2 stabilisation." Human Health section The summary is wrong - see above. Figure 2. re-insert "Note: malaria transmission is assumed to occur within know current mosquito vector distributions" Figure 3. Legend is incorrect Unit for y-axis is per cent change in all-cause mortality rates. Legend should be.. "Percentage change in all-cause mortality rates in 2080s compared to baseline-climate (1961-1990) for five cities as a result of unmitigated emissions (red) and emissions leading to stabilisation of CO2 at 750 ppm (blue) and 550 ppm (green). " Below is the text as it was originally submitted and as it should be included in the final draft. THERMAL STRESS Human populations can be affected directly by their local climatic environment. Mortality peaks are known to occur during heatwaves. However, winter seasonal death rates tend to be greater than summer death rates because thermal stress occurs over a greater temperature range in winter than in summer. Since more deaths occur in winter, changes in future winter temperatures may be the predominant influence on year-round mortality rates. The strongest associations with temperature are for deaths from cardiovascular and respiratory diseases. An empirical-statistical model developed in the Netherlands is here used to estimate the year-round potential impact of climate scenarios on urban population mortality rates. The underlying, city-specific, temperature-mortality response functions have been derived from published epidemiological studies. The model estimates how the expected rise in temperatures due to climate change would affect human mortality for specific age-groups and causes of death. The model estimates both increases in mortality due to warmer summers and decreases in mortality due to milder winters. It assumes that some acclimatisation to warmer weather occurs. However, since there is very little published quantitative evidence about population-level adaptation this is a source of uncertainty in the model. Climate conditions and physiological temperature thresholds of populations differ between locations. The five cities in this assessment represent a range of geographical locations, climate conditions, and levels of development. City-specific climate scenarios were derived (without geographic downscaling) from the Hadley Centre models. Figure 3 illustrates the estimated overall annual benefit of climate warming via reductions in winter mortality rates. However, Guangzhou and Athens would experience an increase in respiratory mortality rates due to hotter summers. In general, both the increases and decreases in mortality are greatest for the unmitigated climate scenario. Although not modelled here, anthropogenic climate change is likely to increase the frequency or severity of heatwaves and decrease the frequency and severity of extreme cold spells. The analysis presented here focuses on the year-round influence of long-term changes in mean climatic conditions upon mortality. Changes in the frequency of extreme thermal events would have an additional, largely separate, effect.