Quantifying the impact of land cover change on regional climate

Ecosystems have garnered much scientific and media attention lately for their potential ability to remove CO2 and other greenhouse gasses from the atmosphere and thereby regulate global climate change.

However, ecosystems can also influence local and regional climate through a different process - biophysical regulation - in which they "mediate the energy and water balances at the land surface."

Now in a new study in the journal Frontiers in Ecology and the Environment, scientists have developed and tested a method to quantify this type of climate regulation by ecosystems.

The goal of this method is to enable resource managers and policy makers to quickly estimate how land cover changes will alter local and regional climate. This is important because in certain areas, changes in land cover may have a bigger effect on regional climate than increases in atmospheric greenhouse gasses.

While past approaches to measure this ecosystem service have included highly complex atmospheric models, this new method aims to be much simpler by using observed climate data and a simple land-surface model.

Paul West and fellow researchers tested the method and found that ecosystems in the boreal and tropical regions have the strongest influence on regulating surface climatic conditions. These findings correspond with the results from more complex models.

The simplified approach, however, does face some limitations. While the method does take into account the influence of wind-transported heat and moisture, it does not fully capture the complexity of different scenarios.

Nevertheless the authors contend that the accessibility of this approach makes it very valuable.  They write, 

"If this simplified approach were incorporated into accessible software tools, ecological researchers and resource managers could make first-order estimates of the effect of land-cover change on air temperature and moisture within minutes, instead of using thousands of computer processor hours. This would enable more rapid assessment of policy and management questions related to the effects of potential land-cover change on biodiversity conservation, agricultural production, and human health. For example, resource managers could quickly generate estimates of changes in air temperature and moisture under alternative land-cover scenarios."

--Reviewed by Rob Goldstein

West, P., Narisma, G., Barford, C., Kucharik, C., & Foley, J. (2010). An alternative approach for quantifying climate regulation by ecosystems Frontiers in Ecology and the Environment DOI: 10.1890/090015