Lyon explores effects of greenhouse gases on tropical sea surface temperature, climate

Bradfield Lyon, a research professor at the University of Maine, wants to understand how sea surface temperature patterns in the tropics may change due to warming caused by increasing greenhouse gases.

Lyon says it’s not just an increase in ocean temperatures that matters, it’s how the warming may differ from one place to another, especially in the tropics.

Spatial variations in tropical sea surface temperatures can lead to shifts in tropical rainfall which, in turn, can alter global wind patterns and regional climates in the United States and around the planet.

The climate is a global system, and changes in one part of the system affect local climate changes in other areas, says the researcher based at the Climate Change Institute.

Thus, accurate information on changes in ocean temperatures is needed in order for models to generate reliable projections of regional climates around the planet.

A major challenge, says Lyon, is that current climate models don’t necessarily capture important aspects of the observed distribution of tropical ocean temperatures, tending to make the ocean too warm in some regions and too cold in others.

These biases need to be taken into account when evaluating regional climate projections.

With a nearly $740,000 three-year grant from the National Science Foundation, Lyon will lead a team of scientists on a project — “Coupled Model Biases in the Sea Surface Temperature (SST) Distribution of the Global Tropics and their Influence on Climate Change Projections” — that will take the biases into account.

The team — a collaboration of researchers at the CCI and The Earth Institute at Columbia University — will evaluate the ability of the latest generation of climate models to simulate key aspects of the observed ocean temperature distribution around the globe.

The team will build a new climate model that minimizes the identified ocean biases then use the new model to produce future climate scenarios under increasing greenhouse gas concentrations.

The project should lead to increased scientific understanding of Earth’s climate and provide groups focused on climate change-related impacts on agriculture and food security with better guidance. The research team is already connected with the Consultative Group on International Agricultural Research, which strives for a food-secure future by working to reduce poverty and improve natural resources.

Through a partnership with UMaine’s RiSE Center, the project also will help foster professional development of Maine high school science teachers. Lyon and collaborators will lead three summer workshops to support Earth science teachers’ use of project-related climate data in their classrooms.

Contact: Beth Staples, 207.581.3777