Early Career: Detection and Attribution of Regional Climate Change with a Focus on the Precursors of Droughts

The goal of this project is to improve understanding of the nature and causes of past changes in droughts to identify potential onset of future drought. The problem of identifying a component forced by climate change is typically addressed using established statistical detection and attribution (D&A) techniques. These techniques identify the characteristic "fingerprints" associated with climate change and connect them to likely causes in the system. However, these techniques have seen little application in drought research because of the noisy nature of the observations in this field. This project, instead of solely focusing on changes in drought characteristics, will investigate the naturally driven and externally forced components of known large-scale drought precursors such as specific ocean temperature patterns or poleward shifts in atmospheric circulation. The research will include an analysis of drought behavior in various climate model simulations and observations; a D&A-derived technique to investigate the temporal changes in major oceanic precursors; an uncertainty quantification analysis based on the 1998-2003 drought; and a rigorous D&A analysis of drought-promoting changes in atmospheric circulation patterns. This research will improve the understanding of drought mechanisms, establish new avenues in regional D&A research, and examine the sensitivity of the results to specific sources of uncertainties in the climate models, in measurements, in the climate drivers, and in the D&A methods. Ultimately, this work will provide scientific underpinning to inform decisions on how society might adapt to droughts in a changing climate.


Project Term: 
2012 to 2017
Project Type: 
Science Focus Area (SFA)

Research Highlights:

Competing Influences on Aridity: Present and future Highlight Presentation
Do Responses to Different Anthropogenic Forcings Add Linearly in Climate Models? Highlight Presentation
Future Loss of Arctic Sea-Ice Cover Could Drive a Substantial Decrease in California’s Rainfall Highlight Presentation
Human and Natural Influences on the Changing Thermal Structure of the Atmosphere Highlight Presentation
Identifying the Human Fingerprint in Observed Cloud Trends Highlight Presentation
Natural and Human Influences on Changing Zonal-Mean Precipitation Highlight Presentation
Observed and Projected Changes to the Precipitation Annual Cycle Highlight Presentation
Observed Multivariable Signals of Late 20th and Early 21st Century Volcanic Activity Highlight Presentation
Regional Contributions of ENSO-Driven Precipitation Variability and Slowly-Evolving Mean Precipitation in the Future Highlight Presentation
Relative Contributions of Mean-State Shifts and ENSO-Driven Variability to Precipitation Changes in a Warming Climate Highlight Presentation
Volcanic contribution to decadal changes in tropospheric temperature Highlight Presentation
Volcanic Effects on Climate Highlight Presentation