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QUEST Deglaciation: Climate and Biogeochemical Cycles during the last deglaciation. Paul Valdes (Bristol) Mary Edwards (Soton), Harry Elderfield (Cambridge), Sandy Harrison (Bristol), Mike Jenkin (Imperial College), Tim Lenton (UEA), Robert Marsh (NOC),
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QUEST Deglaciation:Climate and Biogeochemical Cycles during the last deglaciation. Paul Valdes (Bristol) Mary Edwards (Soton), Harry Elderfield (Cambridge), Sandy Harrison (Bristol), Mike Jenkin (Imperial College), Tim Lenton (UEA), Robert Marsh (NOC), Mark Maslin (UCL), Francis Mayle (Edinburgh), Eolco Rohling (NOC), Dudley Shallcross (Bristol), Alayne Street-Perrott (Swansea), Kathy Willis (Oxford), Eric Wolff (BAS)
The Scientific Challenges: Climate Change through the Deglaciation
The Scientific Challenges: Methane, CO2 and Dust Records through the deglaciation
Overall Goal of Project • To develop a fuller understanding of what has driven changes in climate, atmospheric composition and biogeochemical cycles during the last deglaciation • And to rigorously evaluate process-based Earth system model simulations for this period This is a broad goal so we focus on known key and important processes for which • we have a relatively good basic understanding and modelling capability • And for which we can develop datasets to thoroughly evaluate the modelling
Work Packages • WP0: Project Management • WP1: Palaeodata synthesis • WP2: Model Development • WP3: Baseline LGM and transient simulations • WP4: Modelling Biogeochemical Cycles • WP5: Climate-Biogeochemical Feedbacks • WP6: Model and Data Management Total resource = 23.5 person years Approximately equally divided between data and modelling.
Modelling tools Orographic height Model simulated Mean Annual Precipitation (pre-industrial) FAMOUS HadCM3 • Principal modelling tool will be FAMOUS: • Low resolution version of HadCM3 • Atmosphere is 7.5 x 5 x 11 levels • Ocean is 3.75 x 2.5 x 20 levels (same as HadCM3L) • GENIE used for sensitivity analysis, particularly for fresh water inputs from melting ice sheets.
Storm Tracks are effected by FAMOUS resolution • HadCM3 FAMOUS Storm Tracks in normal and low resolution model
Work Package 2: Model Development Dust cycle modelling Builds upon existing model (potential strong link to QUACC) Sea salt parameterisation Important aerosol and potential proxy for sea ice Extension of “dust modelling” (potential strong link to QUACC) Oxygen Isotopes modelling Develop sub-component model to represent isotopic fractionation during carbonate shell formation (maybe a link to MARQUEST) Completes development of oxygen isotope enabled Hadley model (within HadCM3 family of models) Terrestrial carbon isotopes (possible link to QUERCC) Important for evaluating terrestrial vegetation, methane etc. Atmospheric Chemistry (potential strong link to QUACC) Develop fast chemistry scheme, compatible with UKCA Traceability and tuning FAMOUS + GENIE-IGCM hierarchy
Remaining Work Packages • WP3: Baseline LGM and transient simulations • WP4: Modelling Biogeochemical Cycles • WP5: Climate-Biogeochemical Feedbacks • WP6: Model and Data Management
Stages in Modelling the Deglaciation Phase 1 simulation: Orbital forcing only Phase 2 simulation: As phase 1 + ice sheets + CO2 etc. Phase 3 simulation: As phase 2 + modelled vegetation and fresh water input Phase 4 simulation: As phase 3 + aerosol/chemistry feedbacks
Summary • Project is an ambitious but carefully constructed programme of research that will develop a fuller understanding of what has driven changes in climate, atmospheric composition and biogeochemical cycles during the period since the Last Glacial Maximum. • First transient simulation of deglaciation using a full complexity Earth System model • Development of new model components for dynamically representing key biogeochemical feedbacks • Comprehensive evaluation of model against existing and newly developed datasets. • Cost effective, building upon existing substantial investments by NERC, EU and others. • The “ultimate” test of state-of-the-art Earth System Models.
Relationship to Other Activities • Very strong synergies to other theme 2 proposals and fully complementary to theme 1 projects. • Consortium members have very strong links to Hadley Centre, GENIE, RAPID etc. • Benefits from considerable leverage from ongoing activity including several existing Leverhulme, EU and even some industrial projects
The Scientific Challenges:Charcoal and Fire through the deglaciation
15 kyr BP Lunt (2002) Sensitivity of biogeochemistry to physical climate: Aerosols Dust Pre- Indust. LGM Lunt and Valdes (2002)
Sensitivity of biogeochemistry to physical climate: Methane From Valdes, Beerling, and Johnson. 2005
Project Management Project can only be achieved through a consortium approach. It is also a complex project which requires considerable coordination of tasks to ensure that schedules are maintained. This will be achieved by: • Paul Valdes will coordinate overall project and the modelling tasks • Sandy Harrison will coordinate data synthesis work. • Project coordinator (30%) will manage day-to-day tasks • Regular meetings (4 per year) plus numerous smaller meetings are required to ensure project is on track.
Fit to QUEST QUEST “aims to achieve improved qualitative and quantitative understanding of large-scale processes and interactions in the Earth System, especially the interactions among biological, physical and chemical processes….” The proposal directly addresses the theme 2 call, namely: • “The pattern and controls of variations in processes affecting atmospheric trace gas composition on glacial-interglacial time scales, such as wetland formation, fire frequencies, and changes in terrestrial …..biotic community composition” • “The consequences of changes in the global dust cycle ….”. • “The role of biophysical feedbacks from terrestrial ….. ecosystems in climate change”.
Workpackage 3: Baseline LGM and transient simulation LGM simulation with FAMOUS and GENIE-IGCM Design Transient Simulation Transient simulation with FAMOUS Melt Water Scenarios using GENIE. Evaluation of FAMOUS and GENIE simulations
Workpackage 4: Modelling Biogeochemical Cycles Modelling vegetation, fire, and weland sources of trace gases and aerosol. Modelling dust emissions Modelling sea salt emissions
Workpackage 5: Evaluation of climate-biogeochemistry feedbacks Transient biogeochemical-feedback simulation using FAMOUS Evaluation of FAMOUS simulation Sensitivity analyses using GENIE.
Workpackage 6: Model and Data Management Modelling resources Community access to online web-based database of simulations Data Synthesis Activity All databases will be made available to international community and integrated with modelling resources Long term stewardship in accord with NERC policy.
Modelling ToolsProject will use and enhance • FAMOUS (and other HadCM3 variants) • A Low resolution version of HadCM3 • Advantages: Traceability • Disadvantages: Computational cost (~12 months and ~£150,000 to complete 21,000 years) • GENIE-IGCM (and other GENIE flavours) • A Fully dynamic fast model • Advantages: Better resolution than FAMOUS and more comprehensive biogeochemistry. Computationally relatively fast (~3 months and “cost free” to do 21,000 years ensemble on GRID) • Disadvantages: Less traceable. Control climate currently poorer than HadCM3 (not sure how it compares to FAMOUS). Modules developed for GENIE are not currently simple to then add to HadCM3 suite
Component Models • Oxygen/hydrogen isotopes including forward modelling of forams. Other proxies also to be considered. • Emission modelling of trace gases and aerosols • We will further develop prognostic models of wetlands and fire, and associated emissions schemes. • Develop existing prognostic models for aerosol (dust, sulphate, sea salt) emissions. • Improved modelling of chemistry-climate (within fast framework) • Implementation of the Common Representative Intermediates(CRI) scheme into GENIE, and supplement it with a simple description of secondary organic aerosol scheme. • Closely linked to UKCA and theme 1 activities
Specific Tasks: Datasets • Development of new data synthesis of: • Carbon isotopes from terrestrial sources and • Marine oxygen-isotope data. • Compile new global datasets for: • vegetation changes, • wetland extent (based on sedimentary evidence) and • fire frequency (based on macroscopic charcoal records). • Update existing datasets to improve their temporal coverage.
Specific Tasks: Transient Simulations • Perform a series of continuous time integrations to examine the changes in climate and biogeochemical emissions to investigate the controls on the last deglaciation, using both FAMOUS and GENIE-IGCM • These will initially be forced by reconstructions of ice sheets, GHG’s, meltwater pulses, and orbital changes. • These will be used as a starting point for the biogeochemical modelling • Subsequent simulations will examine the feedbacks from vegetation, aerosols and atmospheric composition. • ALL model simulations will be rigorously evaluated against the extensive new and existing datasets.
Model and Data Management • Model synthesis activities. • All FAMOUS model results will be archived using Bristol model database system (see www.paleo.bris.ac.uk) • Currently holds results from more than 400 model simulations, totalling more than 6 Tb of data (covering all climates from 300 million years ago to future climates) • Allows users to produce plots and animations of more than 1000 different variables, including derived quantities such as biomes. • Currently password protected, with about 100 users. QUEST-Deglaciation will allow it to become fully open. • Data synthesis activities. • The compilation of the terrestrial and oceanic data sets will be coordinated through Bristol, who will provide database and mapping support. • Liaison with the appropriate international data communities will be coordinated through the Data-Model Comparison Subcommittee of PMIP. • The resulting data sets will be made available to the international science community, in conformity with NERC policy on public access to data.
Project Management • Lead PI will be helped by coordinator • Regular (probably 4 monthly) project meetings • Real and Virtual (access grid) • Open to all theme 2 partners • Time management • GANTT diagram to be completed.
Data ToolsProject will expand upon: Extensive existing data syntheses for 6000 and 21,000 yr B.P. • BIOME 6000 • GLOBAL LAKE STATUS DATA BASE • LGM TROPICS • DIRTMAP • TEMPUS SSTs • LGM SNOWLINES
Specific Tasks: Component Models • Oxygen/hydrogen isotopes into Hadley suite of models, and develop proxy models of forams • Changes in vegetation patterns, the extent and productivity of wetlands, and in fire frequency, are important determinants of trace gas emissions during the deglaciation. We will further develop prognostic models of wetlands and fire, and associated emissions schemes. • To investigate the impact of simulated trace gas and aerosol emissions on climate, we will complete the implementation of the Common Representative Intermediates(CRI) scheme into GENIE, and supplement it with a simple description of secondary organic aerosol scheme. • Development of prognostic models for aerosol (dust, sulphate, sea salt) emissions. • Simulated changes in aerosol emissions will be evaluated against existing data sets (e.g. DIRTMAP) and the ice core record. • The dust results will be used by the G-IG proposal to evaluate dust-Fe input into the ocean.
Scientific Motivation:Aerosols and Isotopes Dust and Nitrates Sulphates
Changes in fire regime based on charcoal records from lake sediments
Scientific Motivation:Biogeochemical Cycles Carbon Dioxide Methane Note: Different direction of time axis
Example of Palaeo-wetland map Lakes Wetlands From Hoelzmann et al., 1998
Fresh water events and predictability • Sensitivity to initial conditions. • Same forcing but marginally different basic states. From Renssen et al 2002
Work Package 1: Palaeodata syntheses Continuous reconstructions of changing vegetation patterns Maps and time series documenting changing wetland extent Isotopic composition of terrestrial biomass Semi-quantitative estimates of changing fire regimes based on charcoal
Current availability of pollen sites RESULTS FROM PAIN: Bigelow et al., 2003
WETLAND RECONSTRUCTIONS Mapped patterns e.g. Broström et al., 1998; Hoelzmann et al., 1999 Time series based on basal dates: Canadian Geological Survey database