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The Climate and Earth System Dynamics Group is led by Prof. Noah S. Diffenbaugh. Our research takes an integrated approach to understanding climate dynamics and climate impacts by probing the interface between physical processes and natural and human vulnerabilities. This interface spans a range of spatial and temporal scales, and a number of climate system processes. Much of the group's work has focused on the role of fine-scale processes in shaping climate change impacts, including studies of extreme weather, water resources, agriculture, human health, and poverty vulnerability.

We analyze the present vulnerabilities of natural and human systems to identify the climate phenomena that exert the acute influences on climate-sensitive systems. We then employ a suite of numerical modeling and data analysis techniques to understand why those physical phenomena occur in the current climate, by what mechanisms those physical phenomena are likely to respond to changes in climate “forcing”, and how those physical responses could impact humanity and other life. Employing this approach across a range of climate-sensitive systems has led to insights about (1) the importance of fine-scale climate processes in shaping the pattern and magnitude of climate change, (2) the importance of interactions between physical processes and human dimensions in shaping the impacts of climate change, and (3) the likelihood that high-impact climate change will occur locally and regionally at different levels of global warming.

Our ongoing research activities are directed at answering a suite of specific questions about the interaction of physical climate processes and climate-sensitive systems. These questions include: 

- What are the climate phenomena that most impact natural and human systems? 

- What physical processes control the frequency and severity of those phenomena at present? 

- How do those physical processes respond to changes in forcing of the climate system (such as from changes in greenhouse gas concentrations or variations in Earth’s orbit)? 

- How are natural and human systems likely to be impacted by changes in those physical processes?


Atmospheric Rivers in a Warming Climate

Atmospheric rivers are plumes of concentrated moisture that can induce heavy precipitation upon landfall. The Western US is both reliant on and vulnerable to this extreme moisture transport of atmospheric rivers. How are atmospheric river impacts and characteristics changing with climate change? This project assesses the changing characteristics of atmospheric rivers in the historical era to better understand changes to come.

Improving prediction on subseasonal to multi-decadal time scales

The impact of tropical convection on the midlatitudes is investigated. Simple dynamical model calculations and novel observational techniques are used to show that relatively small differences in the large-scale tropical convection field may lead to marked differences in the extratropical response. This has implications for both medium-range and subseasonal-to-seasonal (S2S) weather forecasting, because significant event-to-event variations in tropical convection occur for Madden-Julian Oscillation (MJO) and El Niño-Southern Oscillation (ENSO) events of the same phase.

Landscape Responses to Climate

Climate change affects the evolution of the Earth’s surface by altering the physical, biological, and geochemical systems that drive surface processes. By examining the signatures of climate on Earth’s surface, this research aims to enhance our fundamental understanding of how landscapes and other surface processes respond to climate forcing, while informing strategies for mitigating the associated environmental and socio-economic impacts.

Precipitation and flooding processes in a warmer climate

Floods are some of the costliest natural disasters, in terms of both property damage and lives lost, in the United States and across the globe. Through this research, we seek to better understand the processes that lead to devastating floods. Additionally, we ask how precipitation and flooding will respond to increased greenhouse gas forcing. A primary goal of this research is to inform adaptation strategies to minimize future damages to human and natural systems.

Precipitation Impacts on Commodity Supply Chain in Developing Regions

Sub-Saharan Africa contains many of the fastest growing population centers in the world. As a result, the food needs of this region are anticipated to grow tremendously in the next few decades, and questions of food security continue to linger in these developing nations. To support these populations, it is critical that local commodity prices are monitored to protect both food and income security in the region.