Peat-based climate reconstructions run into murky waters?

Jul 06, 2012

Peatlands are globally important ecosystems that serve as archives of past environmental change. Peatlands form over thousands of years from the accumulation of decaying plants and hold water, or in some cases purely rainwater. Hence, both external processes, such as climate, and internal processes, such as the rates of peat growth and decay, control the water table in peatlands. However, throughout the previous century and particularly over the past decade, paleoclimatologists have increasingly relied on reconstructions of the water table in rain-fed peatlands to infer changes in rainfall through the Holocene period (the past ~12,000 years), ignoring the potentially important role of internal processes.

But in a new study, Swindles et al. compare paleoecological data from a peatland in England with to show that the in the bogs may change independently of climate. Dynamics inherent in peatland development stabilize the internal environment of the bogs. As a result, the behavior of peatlands can become partially disconnected from external climate influences such as rainfall. The authors further show that water levels in do not respond linearly to changes in rainfall. For example, a two-fold increase in rainfall does not result in a two-fold increase in height of water table in the bogs.

On the basis of these results, the authors caution against indiscriminate use of water table reconstructions in peatlands as indicators of past changes in rainfall. The authors suggest detailed investigation of internal dynamics of peatlands; they call for more studies that combine , paleoenvironmental data, and model results to understand the relative importance of both climate change and internal processes in regulating water tables in peatlands.

Explore further: Researcher studies impact of increased sugarcane production

More information: “Ecohydrological feedbacks confound peat-based climate reconstructions” Geophysical Research Letters, doi:10.1029/2012GL051500 , 2012.

add to favorites email to friend print save as pdf

Related Stories

Storage of greenhouse gasses in Siberian peat moor

Jan 29, 2007

Wet peat moorlands form a sustainable storage place for the greenhouse gas carbon dioxide but are also a source of the much stronger greenhouse gas methane. According to Dutch researcher Wiebe Borren, peat moorlands will ...

Northern peatlands a misunderstood player in climate change

Mar 15, 2011

University of Alberta researchers have determined that the influence of northern peatlands on the prehistorical record of climate change has been over estimated, but the vast northern wetlands must still be watched closely ...

Recommended for you

Water in the Netherlands–past, present, and future

1 hour ago

The storm in the Netherlands began on a Saturday afternoon in February 1953. Ria Geluk, who was 6 years old, told me that it peaked during the night when nationwide communications were on their nightly pause. ...

NASA image: Signs of deforestation in Brazil

21 hours ago

Multiple fires are visible in in this image of the Para and Mato Grosso states of Brazil. Many of these were most likely intentionally set in order to deforest the land. Deforestation is the removal of a ...

Sunblock poses potential hazard to sea life

22 hours ago

The sweet and salty aroma of sunscreen and seawater signals a relaxing trip to the shore. But scientists are now reporting that the idyllic beach vacation comes with an environmental hitch. When certain sunblock ...

User comments : 1

Adjust slider to filter visible comments by rank

Display comments: newest first

NotParker
3.7 / 5 (3) Jul 06, 2012
The real authors of all climate change papers:

Swindles et al.

Perfect.