Method

In this collaborative project between UKCEH and the University of Leeds we will use data from satellites and the latest weather and climate models to get to the heart of how vegetation affects rainfall. Focusing on West Africa, we will examine cloud and vegetation observations from the last 30 years to detect where deforestation has changed rainfall, and how the rapid greening of the savannah each year affects the monsoon rains.  We will perform new computer simulations, incorporating the detailed development of thousands of individual storms, and examine what happens when we artificially deforest a region in the model. We will examine how the less-detailed computer simulations used for climate change projections actually capture the effects of vegetation.

Image
Forested region of Tai National Park, image NASA Worldview
Image
Cloud free area above Tai National Park, image NASA Worldview

Above left: The forested region of Tai National Park (centre of the image) in a cloud-free satellite image. Image source: NASA Worldview.
Above right: Cloud-free area above the northern part of Tai National Park and forested regions to the west. Image source: NASA Worldview.

Results

We have found from analysis of satellite observations that deforestation in Southern West Africa has enhanced storm frequency over the last 30 years. The effect is particularly strong in coastal areas, where post-deforestation warming enhances land-sea breezes which are a key driver of storms. See our article in The Conversation, or look at the paper in PNAS.

 

 

Principal Investigator