Identifying Grand Challenges in Climate Change Research: Guiding DOE’s Strategic Planning: Report on the DOE/BERAC workshop March Crystal City For BERAC meeting 20 May

Meeting summary  About 60 Participants – about half from DOE labs and half from universities and other Federal labs.  Mix of plenaries and breakout sessions.  Organized based on Orbach’s charge letter – seen in agenda in appendix but not repeated as not used as framing for the challenges recommended.

Process of report preparation  Initial content agreed to by a drafting group meeting the afternoon following the workshop  Written by the co-chairs and iterated many times with a subset of the workshop participants.  The reports overall message appears to have converged.  However, it still needs to be looked at by the BERAC and the other workshop participants who have not yet seen it (comments through the latter better done from a closed interactive website).

Background to the meeting  Climate change from use of fossil fuel energy recognized by DOE as a major constraint on the Nations future development and use of energy.  IPCC 2007 reported that this climate change already highly visible and expected to continue unabated for at least the next several decades.  Since that report, a number of further studies showing some changes happening even faster than anticipated.  A chorus of voices asking for more detailed local information on what has and will change for their planning horizons  NOAA planning on providing a “Climate Services” to meet this need with there yet being little of the research being done that such a “Services” would have to be built upon.

Grand Challenges Identified by the Workshop  Improve the characterization of Earth’s climate, and its evolution through the last century to its present state.  Predict regional climate change for the next several decades.  Simulate Earth System change over centuries.

Translation into DOE science strategy  Report implies that much of DOE’s current climate science program needed.  But shift in emphasis called for to realign to fit current scientific and political reality of need for useful climate information.  Obtaining and disseminating such information is a hugh task with a large practical component – “climate services” – but such needs to be informed by a research program that DOE can be a major contributor to.

Improve the characterization of Earth’s climate, and its evolution through the last century to its present state.  A high-dimensional dynamical system – individual observations are snapshots of components are particular times and place - do not recognize the interconnectedness.  NWP provides a prototype what is needed. Through statistical modeling, combine multiple streams of observations with model predictions to optimally describe system.  Reanalyses go back in time using a single consistent model.  Provide global system research data sets and initial conditions for future projections.  Improves with improvement of the model process descriptions.

Predict Regional Climate Change for the Next Several Decades  Much more climate detail can be provided by –Use of latest high performance computational tools. – limiting time frame to decadal and processes to those that are important on that time frame.  Additional information if initial state adequately constrained by observations – expected product from the first Challenge.

Simulate Earth System change over centuries  On century time scales many feedbacks affect climate system that are not yet modeled or adequately so (e.g., involving biogeochemical cycling, dynamic vegetation, and atmospheric chemistry).  Carbon cycle feedbacks have large control on how much atmospheric CO2 over this time.

Research areas needed to address Grand Challenges- each area has 3-components  Characterize the Earth’s present climate.  Predict climate over the next several decades.  Simulate Earth System change over centuries.

Characterize impacts of radiatively active constituents-aerosols and atmospheric chemistry  Current radiative forcing-regionally specific -attribution of current observed patterns?  How affect clouds?  Analysis and assimilation of observations into models.  How will forcing change regionally in the next several decades?  Changes over century of aerosols and other radiative forcing from human and natural causes and feedbacks with climate change.

Interactions between ecosystems and climate  What are the appropriate state variables for Earth System models?  What and how do natural and managed ecosystems contribute to atmospheric composition?  Spatial data sets needed to represent in Earth System models.  How will ecosystems be impacted by and contribute to climate change and air quality change regionally over next few decades?  Changes and feedbacks on century time scale?

Interactions between climate change and management of hydrological systems  Regional climate impact of land use/land cover change?  How incorporate impacts of climate change on water management?  Eliminate persistent biases in simulated regional predictions.  quantitative measures of ability to predict changes in extreme precipitation probabilities.  Changed frequencies of floods and droughts?  How temperature change affected by changing soil moisture and land cover?

Earth System Modeling  Plan and develop next/multiple generations  Incorporate advances in process understanding to further model complexity and improve parameterizations-e.g. clouds.  Develop and improve/validate initialization procedures.  Resolve cloud processes.  Provide regional details to integrated assessment models.  Use next generation of emission scenarios to project Earth System on century scale.

Energy Systems and Climate Change  Most promising near term strategies for reduction of carbon emission?  How will climate change and mitigation efforts impact national economies over the next several decades?  Vulnerable sectors of society?  What adaptation strategies should we be putting in place?

Emphases implied for DOE climate program  Better inform modeling activities through DOE’s climate observational programs (ARM, aerosol, carbon, ecology…) needed interfaces currently missing?  Connect integrated assessment modeling to climate modeling – recognize in general major human dimensions elements that involve research questions.  Will require training/education of many more scientists.

Directions Highlighted  Grand Challenges include the integration and communication of many improved and improving kinds of scientific information into overall assessment of how climate is changing.  Physical processes, options for mitigation and adaptation.  New research, computational, observational, and experimental directions needed.  Directly related to and facilitated by enhanced computing capabilities.  Large multiyear field program needed?  Several workshops to develop more details.