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What Drought Science Says about Drought Predictions and Projections. Christopher J. Anderson, PhD Assistant Director, Climate Science Program Iowa State University. Midwest Climate Collaboration Meeting 21-22 August 2012. 2012 Drought Resembles Past Droughts.
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What Drought Science Says about Drought Predictions and Projections Christopher J. Anderson, PhD Assistant Director, Climate Science Program Iowa State University Midwest Climate Collaboration Meeting 21-22 August 2012
2012 Drought: A large departure from recent trends • Recent June-August maximum temperature has been below the 20th Century average. • Recent June-August rainfall has been above the 20th Century average.
2012 Drought: Natural variability in a warming world creates larger year-to-year variability
Expect Sea Surface Temperature to Change • If we project decadal changes using historical performance, then… AMO becomes negative 2025-2030.
Expect Sea Surface Temperature to Change • If we project decadal changes using historical performance, then… PDO becomes positive 2020-2025.
Expected Drought Risk Based on Historical Performance 2020-2030
Caveat: 2020 and Beyond has Larger Uncertainty • While historical performance is the best available guidance for 2020-2030, a systematic approach for blending recent trends and past performance is lacking. • How closely will 2020-2030 resemble the past given the recent trends?
Climate projections indicate Warm-Dry AND Warm-Wet Summers are possible
Caveat: 2020 and Beyond has Larger Uncertainty • While historical performance is the best available guidance for 2020-2030, a systematic approach for blending recent trends and past performance is lacking. • How closely will 2020-2030 resemble the past? • Beyond 2030, the warming climate will have an increasingly greater impact on variability and the range of possible conditions is broader.
Good News: Seasonal Predictions of Summer Drought are more skillful • Skill of June-August forecast made with NOAA CFSv2 is 0.7-0.8. Wei et al. (J. Appl. Meteor. Clim. 2012)
Good News: 2012 CFS forecast of near record July warmth for Iowa
Improvements in Seasonal Forecasts mayenable tests of adaptive strategiesAdaption: Adjustment in natural or human systems in response to actual or expected climate stimuli or their effects, which moderates harm or exploits beneficial opportunities.
Resistance-Resilience-Transformation Adaptation Framework Resistance Strategies Maintain the status quo over the near term through management that builds resistance to climate change Resilience Strategies Longer-term actions that build adaptive capacity by improving the system’s ability to moderate effects of climate Transformation Strategies Increase adaptive capacity by facilitating the transition to a new system with different structure and function better adapted U. S. Forest Service, 2010
Development of Adaptive Actions for Agriculture • La Niña means risk of yield loss is higher. • La Niña forecasts provide 3 to 6 months advanced guidance for crop insurance and crop variety selections. • Resistance Adaptation
The 2012 Drought with Heat Wave is evidence that the combination of natural and forced climate changes will amplify year-to-year variability in the Midwest. • Resistance adaptation strategies may be tested with existing seasonal forecasts due to new predictive capabilities for seasonal drought forecasts. • Resilience and transformative strategies require development of novel projection techniques to infer potential changes in year-to-year variability.