Improving MOdelling approaches to assess climate change-related THresholds and Ecological Range SHIfts in the Earth's Peatland ecosystems (MOTHERSHIP)

Lead Research Organisation: University of Exeter
Department Name: Geography

Abstract

Peatlands form in wet environments where the organic matter built up by plants every year is not fully degraded. This means that, over time, partly degraded organic matter accumulates as peat locking away huge quantities of carbon. We call such areas 'carbon sinks' and through this process, peatlands moderate the Earth's climate. When carefully managed they are our most carbon-rich ecosystems on land. Unfortunately, due to poor management, they are currently our most intensive source of carbon dioxide emissions from land, amplifying climate change in the same way as burning fossil fuels.

The primary means by which peatlands are damaged is drainage, which lowers the water table. This changes how peatlands function, and as a consequence, such areas switch from carbon sinks to carbon sources. Around the world, 10-15% of all peatlands have been impacted by drainage, and use as cropland, production forests, and grazing. In the UK and more widely across Europe, so many peatlands have been altered that >50% of former peat accumulating habitat has been lost.

As part of the effort to reduce global emissions, governments across Europe have invested significant sums in peatland restoration efforts, however it is unclear whether these efforts will be successful in the light of climate change, particularly increasing global temperature and changes to rainfall patterns. In this project, we will investigate whether degraded peatlands differ from natural peatlands in the way they react to climate change. Using sites across the European climate gradient, we will examine what effect variations in weather over several years have on GHG emissions from natural and disturbed peatlands. Using a regional-to-global scale model to simulate future weather to 2100, we will use our new information to enable better policy decisions to sustainably manage peatlands. This will be achieved in the following way:

First, we will determine how differences in climate and management affect how peatlands function, using measurements from 44 micrometeorological stations and thousands of satellite (Earth Observation) data points across Europe. The satellite data will enable us to understand processes on a far larger landscape scale than the field data. We will also use satellite data to determine the physical up-and-down movement of 15 exemplar peatlands relative to climatic drivers, as this is an important mechanism by which peatland water tables self-regulate. We will then model fine-scale water flows across these 15 landscapes to estimate how climate, vegetation and water flows interact in peatlands.

Second, using the above observations and models we will develop and test a peatland version of a regional- to global-scale model: the Joint UK Land-Environment Simulator (JULES). JULES can model what happens to our environment under climatic change across the globe, but currently is unable to deal with peatlands.

Finally, with the new JULES-PEAT model, we will be able to predict how UK and European peatlands will behave under climate change and current land use, and what strategies should be taken to minimise future carbon losses. We will develop scenarios of such strategies with our project partners and run a series of international workshops to compare the new JULES-PEAT model against other global climate models, in order to advance better global forecasting of climate change effects on peatlands as a whole and to find the best possible future management solutions for peat soils to mitigate climate change. Working with partners with UK/EU policy links, this will provide solid data for future peatland policies and management on the ground.

Publications

10 25 50