Area 4: Assess Natural Systems Response

For description of this technical area and for the context on how this area fits into the outline of technical areas for incorporating climate change information into water resources assessments, please see our Long-term climate change research activities.

. These areas were featured in discussion of desired versus current capabilities in Addressing Climate Change in Long-Term Water Resources Planning and Management: User Needs for Improving Tools and Information (pdf 8MB). The result from that discussion are a listing of research needs, or "gaps", under eight technical areas. After compiling this list, a process followed where relative research priorities were assigned to each gap (low, medium and high). The second and third columns of the table indicates priority ratings reflecting pooled views from Reclamation and USACE only, and pooled views from all document reviewers, respectively. The fourth column lists the research activities being supported by Reclamation's Research and Development Office associated with these gaps.

Technical Planning Steps and Associated Gaps in Tools and Information	Priority Ranking1		Activities
	Reclamation/ USACE	All Respondents	Activities
4.01 Guidance on strengths and weaknesses of watershed hydrologic models/methods to support scoping decisions in planning.	Low	Low	2011 1646 Sensitivity of Hydrologic Impacts Assessment to Downscaling Methodology and Spatial Resolution 2009-2010 2404 Climate Change: Assessing Preference Among Surface Water Hydrologic Models for Studies Involving Climate Change 2009-2010 2726 Climate Change: Erosion of Water Supply Predictability Under Climate Change? 2006-2007 6253 Assessing the Risks of Shifting Climate on Water and Power Operations in Reclamation Regions See publications.
4.02 Understanding how climate change should impact potential evapotranspiration and how it is represented in watershed hydrologic models.	High	High
4.03 Method and basis for estimating extreme hydrologic event possibilities, deterministically or probabilistically, in a changing climate. (Similar to Gap 3.06 but focused here on hydrology rather than meteorological variables)	High	High	2008 -2010 Directed: Assessing Flood Frequency in a Changing Climate . See publications. Directed: Post-doctoral Resarch Support (Project 1. Assessing the potential for changes in warm season extreme precipitation events across the Colorado Front Range in future climates)
4.04 Guidance on strengths and weaknesses of available versions of spatially distributed hydrologic weather data that may be used for both watershed hydrologic model development (Step 4) and in climate model bias-correction (Step 2).	Medium	Medium	2011 675 Understanding How Different Versions of Distributed Historical Weather Data Affect Hydrologic Model Calibration and Climate Projections Downscaling
4.05 Understanding how climate change should impact groundwater recharge and groundwater interaction with surface water supplies.	Medium	Medium	2009 2885 Climate Change: Methodology to Evaluate the Influence of Joint Changes in Climate and Land Cover on Water Availability 2011 - present Directed: Groundwater and Surface Water Interactions
4.06 Understanding how climate change should impact inland and coastal anadromous fisheries.	Medium	Low	2011 5891 Biological Impacts on Reclamation Operations from Climate Change 2011 6507 Evaluating Climate-Induced Runoff and Temperature Change on Stream Habitat Metrics for Endangered or Threatened Fish 2011 1158 Physiological Tolerances of Fishes of the Sacramento-San Joaquin Delta, California
4.07 Understanding how climate change may impact riparian ecosystems and vegetation that affect both longer-term water budgets and ecological resources.	High	Medium	2011 6507 Evaluating Climate-Induced Runoff and Temperature Change on Stream Habitat Metrics for Endangered or Threatened Fish 2010-2011 310 Effects of Climate Change on Riparian Vegetation Structure, Water Uptake, and Dependent Pollinators along Mainstem Rivers in the Colorado River Basin
4.08 Understanding translated into model frameworks for assessing climate change responses for fisheries, nonnative riparian vegetation, and other species or habitat conditions.	High	Medium	2011 3821 Climate Change: Application of HydroGeoSphere (HGS) Thermal (Temperature) Modules for Evaluation of The Impacts of Climate Change on Water Resources and Fish Ecosystems
4.09 Understanding how climate and/or carbon dioxide changes should impact land cover communities that control natural evapotranspiration and soil erosion potential.	Medium	Low	2009-2010 2768 Climate Change: Methodology to Evaluate the Influence of Joint Changes in Climate and Land Cover on Water Availability
4.10 Understanding how water quality characteristics depend on climatic variables and how dependencies may evolve in a changing climate.	High	High
4.11 Understanding how climate and carbon dioxide changes should impact plant physiology, how impacts vary with crop type, and how impacts affect irrigation demand.	Medium	Medium
4.12 Understanding how climate and/or land cover changes will change watershed sediment yield, changes in sediment constituency, and the resulting impacts on water resources.	Medium	Medium	2010-2011 8990 Investigation of Climate Change Impact on Reservoir Capacity and Water Supply Reliability
4.13 Understanding how climate, land cover, and/or sedimentation changes will affect river and reservoir ice-event potential.	Medium	Low

Publications and peer review reports:

(Gap 4.01) Maurer, E.P., L.D. Brekke, and T. Pruitt (2010), Contrasting lumped and distributed hydrology models for estimating climate change impacts on California watersheds. Journal of the American Water Resources Association (JAWRA) 46(5):1024–1035. DOI: 10.1111/j.1752-1688.2010.00473.x.

(Gap 4.03) Raff, D.A., T. Pruitt and L.D. Brekke (2009). “A framework for assessing flood frequency based on climate projection information.” Hydrology and Earth System Science Journal. Vol. 13, p. 2119–2136.