Peatlands and the global carbon cycle during the past millennium: a global assessment using observations and models
Lead Research Organisation:
Imperial College London
Department Name: Life Sciences
Abstract
Future climate change is one of the most challenging issues facing humankind and an enormous research effort is directed at attempting to construct realistic projections of 21st century climate based on underlying assumptions about greenhouse gas emissions. Climate models now include many of the components of the earth system that influence climate over a range of timescales. Understanding and quantifying earth system processes is vital to projections of future climate change because many processes provide 'feedbacks' to climate change, either reinforcing upward trends in greenhouse gas concentrations and temperature (positive feedbacks) or sometimes damping them (negative feedbacks). One key feedback loop is formed by the global carbon cycle, part of which is the terrestrial carbon cycle. As carbon dioxide concentrations and temperatures rise, carbon sequestration by plants increases but at the same time, increasing temperatures lead to increased decay of dead plant material in soils. Carbon cycle models suggest that the balance between these two effects will lead to a strong positive feedback, but there is a very large uncertainty associated with this finding and this process represents one of the biggest unknowns in future climate change projections. In order to reduce these uncertainties, models need to be validated against data such as records for the past millennium. Furthermore, it is extremely important to make sure that the models are providing a realistic representation of the global carbon cycle and include all its major component parts. Current models exclude any consideration of the reaction of peatlands to climate change, even though these ecosystems contain almost as much carbon as the global atmosphere and are potentially sensitive to climate variability. On the one hand, increased warmth may increase respiration and decay of peat and on the other hand, even quite small increases in productivity may compensate for this or even exceed it in high latitude peatlands. A further complication is that peatlands emit quite large quantities of methane, another powerful greenhouse gas. Our proposed project aims to assess the contribution of peatlands to the global carbon cycle over the past 1000 years by linking together climate data and climate model output with models that simulate the distribution and growth of peatlands on a global scale. The models will also estimate changes in methane emissions from peatlands. In particular, we will test the hypotheses that warmth leads to lower rates of carbon accumulation and that this means that globally, peatlands will sequester less carbon in future than they do now. We will also test whether future climate changes lead to a positive or negative feedback from peatland methane emissions. To determine how well our models can simulate the peatland-climate links, we will test the model output for the last millennium against fossil data of peat growth rates and hydrological changes (related to methane emissions). To do this, we will assemble a large database of published information but also new data acquired in collaboration with partners from other research organisations around the world who are involved in collecting information and samples that we can make use of once we undertake some additional dating and analyses. Once the model has been evaluated against the last millennium data, we will make projections of the future changes in the global carbon cycle that may occur as a result of future climate change. This will provide a strong basis for making a decision on the need to incorporate peatland dynamics into the next generation of climate models. Ultimately we expect this to reduce uncertainty in future climate change predictions.
Organisations
People |
ORCID iD |
Colin Prentice (Principal Investigator) |
Publications
Adams GL
(2013)
Diatoms can be an important exception to temperature-size rules at species and community levels of organization.
in Global change biology
Banks-Leite C
(2011)
Decisions on Temporal Sampling Protocol Influence the Detection of Ecological Patterns
in Biotropica
Banks-Leite C
(2011)
Comparing species and measures of landscape structure as indicators of conservation importance Species vs. landscape-based indicators
in Journal of Applied Ecology
Banks-Leite C
(2012)
Unraveling the drivers of community dissimilarity and species extinction in fragmented landscapes.
in Ecology
Charman D
(2013)
Climate-related changes in peatland carbon accumulation during the last millennium
in Biogeosciences
Gallego-Sala A
(2018)
Latitudinal limits to the predicted increase of the peatland carbon sink with warming
in Nature Climate Change
Gallego-Sala A
(2012)
Blanket peat biome endangered by climate change
in Nature Climate Change
Gallego-Sala A
(2015)
Climate-driven expansion of blanket bogs in Britain during the Holocene
Gallego-Sala A
(2016)
Climate-driven expansion of blanket bogs in Britain during the Holocene
in Climate of the Past
Hudson L
(2012)
Cheddar: analysis and visualisation of ecological communities in R
in Methods in Ecology and Evolution
Description | My findings have not yet been used but I am in touch with relevant people in NGOs and the Brazilian government to put some of these results in practice. |
Sector | Environment |
Description | Coverage for research on New York Times website |
Form Of Engagement Activity | A magazine, newsletter or online publication |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Public/other audiences |
Results and Impact | Microscopic Neighbors, Evolving Together It seems obvious that how different living things in a community or ecological system bump up against one another would affect how they evolve. That would include everything from the mix of fish in a lake to the bacteria, fungi and insects that coexist in rainwater that pools in the roots at the base of a beech tree... Readers of the website found out about this research |
Year(s) Of Engagement Activity | 2012 |
URL | http://www.nytimes.com/2012/05/16/science/microscopic-neighbors-evolving-together.html?_r=0 |
Description | Hengill Documentary |
Form Of Engagement Activity | A press release, press conference or response to a media enquiry/interview |
Part Of Official Scheme? | No |
Geographic Reach | National |
Primary Audience | Policymakers/politicians |
Results and Impact | Resulted in a documentary on the ecological importance of geothermal areas This documentary has been used to discourage geothermal energy expansion in Iceland by highlighting the ecological importance of these areas |
Year(s) Of Engagement Activity | 2012 |
Description | Keynote at AGU Dec 2019: Planetary drivers of carbon accumulation in peatlands by Angela Gallego-Sala |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Professional Practitioners |
Results and Impact | A keynote presentation given on Peatlands at the American Geophysical Union convention in San Francisco in December 2019. This conference attracts researchers and practitioners from around the world (in the region of 24,000 participants). |
Year(s) Of Engagement Activity | 2019 |
URL | https://agu.confex.com/agu/fm19/meetingapp.cgi/Paper/548642 |
Description | Keynote presentation: Global peatland carbon: challenges and opportunities by Angela Gallego-Sala at the Leeds Quaternary Research Association |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | National |
Primary Audience | Professional Practitioners |
Results and Impact | A keynote presentation given by team member Angela Gallego-Sala entitled Global peatland carbon: challenges and opportunities at the Quaternary Research Association Annual Discussion Meeting hosted by Leeds Quaternary at the University of Leeds. |
Year(s) Of Engagement Activity | 2020 |
Description | Millipeat Workshop (Devon, UK) |
Form Of Engagement Activity | Participation in an activity, workshop or similar |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Professional Practitioners |
Results and Impact | In December 2015, 13 experts from a range of locations (multiple UK locations plus Germany and America) attended a workshop jointly organised by Prof Iain Colin Prentice (Imperial College London) and Dan Charman and Angela Gallego-Sala (Exeter University). The aims of the workshop were to: 1) Address and discuss the research (data collection and model development) done so far in association with the Millipeat project 2) plan model experiments with LPX-Bern and a data model comparison strategy 3) To develop a publication road map 4) to brainstorm ideas for future research, proposals and projects in the broader field of peatland dynamics and the role of peatlands in influencing global climate, past, present and future. |
Year(s) Of Engagement Activity | 2015 |
Description | Planet Earth article |
Form Of Engagement Activity | A magazine, newsletter or online publication |
Part Of Official Scheme? | No |
Geographic Reach | National |
Primary Audience | Public/other audiences |
Results and Impact | Article has received positive feedback in social media |
Year(s) Of Engagement Activity | 2014 |
URL | http://planetearth.nerc.ac.uk/features/story.aspx?id=1749 |
Description | Public engagement at Science Uncovered event at the Natural History Museum, 28th September 2012 |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | Yes |
Geographic Reach | International |
Primary Audience | Public/other audiences |
Results and Impact | Public learned scientific information about microbial diversity and evolution in the context of digestive health Public expressed interest and learned new facts |
Year(s) Of Engagement Activity | 2012 |
Description | Science Uncovered - Natural History Museum (September 2013) |
Form Of Engagement Activity | Participation in an activity, workshop or similar |
Part Of Official Scheme? | Yes |
Geographic Reach | National |
Primary Audience | Schools |
Results and Impact | Science Uncovered is a widely-advertised and well-attended public outreach event hosted at the Natural History Museum in London, where scientist engage with the public face-to-face basis to discuss their research and its implications in an informal setting. I represented Imperial College London, accompanied by two PhD students, and discussed my group's work, which included the current grant, under the general theme of ecological responses and alterations to energy flux in food webs due to environmental stressors. At our stall we spoke to several hundred visitors throughout the day. See description above. |
Year(s) Of Engagement Activity | 2013 |
Description | Website highlighting research on the model system in Iceland |
Form Of Engagement Activity | A magazine, newsletter or online publication |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Public/other audiences |
Results and Impact | https://sites.google.com/site/hengillresearch/ Numerous Skype discussions with potential collaborators, and the preparation of a NERC Large Grant bid |
Year(s) Of Engagement Activity | 2013 |
URL | https://sites.google.com/site/hengillresearch |