The Use of the Community Earth System Model in Human Dimensions Climate Research and Applications

Emily Laidlaw & Brian O’Neill – NCAR/CGD & Ryan Harp – University of Colorado/ATOC 22nd Annual CESM Workshop, SDWG meeting, June 22, 2017

“Human dimensions climate research and applications”

Research or applications whose results are directly relevant to improving understanding of how society contributes to climate change, is influenced by it, or takes action to respond to it.

Considered:• Human dimensions‐related goal in title or abstract• Source of publication• Primary audience• Literature sent to us

AN IMPORTANT DEFINITION

To fulfill SDWG mission to improve CESM development and application at intersection of human & earth systems, need to quantify how CESM is used. 

• In what research areas is CESM used?• Is the use of CESM growing over time?• How often used for physical vs societal assessments?• Mostly single simulations? Multi‐model ensembles?• Downscaled? Bias corrected?• Global vs regional vs local analysis?• Areas where use could be improved?• Areas where not used?

MOTIVATION

PROCESS

Defined boundaries

Defined terms

Developed framework

Selected collections

3‐tiered review process

General literature review

2,412 67 relevant

CESM Pubs List

27,930 141 relevant

IPCC AR5

WG1&2

472 36 relevant

CLM Pubs List

20 16 relevant

CHSP BRACE Project

14,512 23 relevant

IPCC AR4

WG1&2

N/A 57 relevant

General Lit

Review

• 2004‐2016 ‐ CCSM3, CCSM4, CESM1• 45,346 (+ gen lit review) publications considered• 340 articles met criteria for analysis

FRAMEWORKBasic 

InformationTitleAuthorLinkDOIAffiliationSourceYearSummaryNotes

Systems & Outcomes

SocietalHealthEnergy use

Managed CropsLand Use

EcosystemBiodiversitySpecies Range

PhysicalSea level riseExtremes

Research Area

ImpactsEmissionsMitigationAdaptationFramework

Model & Related DetailsModel versionResolutionComponentSimulation typeTimeframeScale

Biodiversity Species range Ecosystem viability

ECOSYSTEMS

HealthEconomyEnergy usePoliciesConflictFood SecurityTransport

SOCIETAL SYSTEMSCrops

Managed waterManaged forests

Urban areasLand use

Land cover

MANAGED SYSTEMS

AerosolsDrought

Sea level rise Temperature extremesPrecipitation extremes

Tropical cyclonesHydrologic cycle

Global/regional temp

PHYSICAL SYSTEMS

SYSTEMS CATEGORIZATION

Impacts of population changes on exposure to Aedes aegypti(A. Monaghan)

Climate change impacts on biodiversity and rubber production(R. Zomer)

The importance of aerosol scenarios in projections of future heat extremes (Y. Xu)

Estimated impacts of emission reductions on wheat and maize crops (C. Tebaldi)

CESM USE BY PRIMARY SYSTEM

AR4 deadline

AR5 deadline

0

10

20

30

40

50

60

70

2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016

Physical systemManaged systemSocietal systemEcosystem

CESM USE BY PRIMARY SYSTEM

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016

Physical systemManaged systemSocietal systemEcosystem

PRIMARY OUTCOMES BY SYSTEM

CESM USE BY RESEARCH AREA

AR4 deadline

AR5 deadline

0

10

20

30

40

50

60

70

2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016

FrameworkEmissionsMitigationAdaptation

Impacts

MODEL VERSION

0

10

20

30

40

50

60

70

80

2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016

CCSM3 release

CCSM4 release

CESM1 release

CCSM4CESM1

CCSM3

TYPE OF SIMULATIONS

AR4 deadline

AR5 deadline

0

10

20

30

40

50

60

70

2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016

Single simulationsSmall multi‐model ensemble

Initial condition ensemble

Large multi‐model ensemble

SCALE OF ANALYSIS

AR4 deadline

AR5 deadline

0

10

20

30

40

50

60

70

2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016

RegionalLocal/City

Global

TIMEFRAME

AR4 deadline

AR5 deadline

0

10

20

30

40

50

60

70

2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016

Decadal (pre‐2050)Beyond 2100

2050‐2100 (50‐100year projections)

DOWNSCALING & BIAS CORRECTION

• Downscaling typically corresponded with regional studies• Bias correction often corresponded with downscaling• Downscaling most common for managed and physical systems• Bias correction most common for physical systems• Most commonly downscaled and bias corrected outcomes included 

managed water, crops, hydrologic cycle, and health• Papers on extremes frequently bias corrected

73% not bias corrected

27% bias corrected

72% not downscaled

28% downscaled

FIRST AUTHORSHIP

1

5

12

19

42

53

67

141

0 20 40 60 80 100 120 140 160

Africa

South America

North America

Australia/Oceania

Asia

NCAR

Europe

Non‐NCAR U.S.

• Primary CESM use for physical systems with societal relevance; temp + precip extremes

• Use for managed systems and societal systems increasing over time; importance of CLM

• CESM primarily used for 50‐100 year impact studies as part of large multi‐model ensembles

• Sporadic use for ecosystems and adaptation‐focused research

• Commonly downscaled and bias corrected: Crops, Managed water, health, hydrologic cycle

• CESM first authors commonly U.S.‐based, university‐affiliated

SUMMARY

• Increasing use of CESM for managed and societal systems suggests more/better focus on relevant components of the model

• Should CESM be used for:• Ecosystems research• Adaptation‐focused research• Timeframes past 2100

• If so, consider how working group can better facilitate these connections

• Continue to track use of CESM in human dimensions work

RECOMMENDATIONS

• Further interpretation of results• Journal paper

• Proposal submitted• Website

• Database available online• Request CESM2 submissions

NEXT STEPS

FEEDBACK, QUESTIONS, COMMENTS WELCOME

THANK YOU!

EMILY LAIDLAWASSOCIATE SCIENTISTIntegrated Assessment Modeling GroupClimate and Global Dynamics LaboratoryNational Center for Atmospheric ResearchEmail: laidlaw@ucar.edu