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Core Project3. Assessment of climate risk based on integrated climate, impact, and land use models |
Research Plan > Core Research Projects > 2009 Research Results |
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[2009 Research Results] |
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The impact of heat stress on human health |
We conducted a risk assessment of the global warming impact on human health in terms of the number of excess mortality induced by heat stress using future climate projection scenarios by 20 GCMs adopted in the IPCC AR4. The large variability found among the estimations derived from different climate scenarios implies that an estimation just based on the model-average would be insufficient for discussing appropriate adaptation options. |
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Excess mortality induced by heat stress |
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Excess mortality due to heat stress in (a) the present climate (1971-2000) and (b) future climate (2071-2100; model-mean), as well as (c) regional average of change in excess mortality (model-median and 5-95% range) are shown in this figure. Outputs of 17 GCMs driven by the SRES-A2 emission scenario were used. Globally, excess mortality is estimated to increase by about 335% (135-407%) during the 21st century. |
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Analyzing and constraining the uncertainty of water resource impact assessments
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Assessments of water resource impacts in South America are very sensitive to the model uncertainty of climate change projections. Panel (e) shows the model-averaged assessment. In a naïve argument, this model-averaged assessment is the best estimate, but is it really true? We revealed the physical causes of the uncertainty of impact assessments, and pointed out that the estimate in panel (c) is more reliable than the model-averaged assessment. These findings have great implications for water resource management and for the assessment of ecosystem impacts. |
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Uncertainties of annual mean runoff changes in South America |
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Panel (e) shows the model-averaged assessment. These model uncertainties are associated with intensities of atmospheric zonal and meridional circulations in the present climate. Our evaluation indicated that the estimate in panel (c) is the most reliable assessment. |
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Development of global agricultural land scenarios |
In the Land-Use Change Model team, we developed spatially detailed scenarios for RCP (Representative Concentration Pathways), which constitute the basis of IPCC's new scenario. A high resolution scenario of the future urban area distribution was developed considering population, GDP, and urbanization ratio. A new scenario of biomass-crop was created. Furthermore, the precision of the simulation in the base year was improved. In the previous map aggregation, a decision-by-majority approach was adopted. Here, we present a revised map aggregated using ground-based validation data. This new map has a κ statistics of 0.66; and shows higher accuracy in comparison with other maps with κ statistics of 0.62. |
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Fraction of the total land occupied by cropland |
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The figure above shows the distribution of cropland fraction estimated by a land-use model on the basis of the RCP 6.0 (target +6W m‾ ² radiative forcing) scenario. |
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