Water in the West - Session 3 - Mike Hightower

Management of Forest Ecosystems to Improve Water Availability and Ecological Resilience in the West

Mike Hightower

Sandia National Laboratories

Albuquerque, NM 

Laura McCarthyThe Nature ConservancyNew Mexico Field Office

Transformational Solutions for Water in the WestUniversity of New Mexico, September 5, 2013

Climate Change will Impact Precipitation, Evapotranspiration, and Runoff

“Water is where the climate change rubber meets the road”Dr. Bernie Zak, Sandia Sr. Climate Scientist, 2013

Nat. Geo. April 2009 from IPCC

10% reduction in precipitation equals a 20% reduction in runoff in the SW

Southwest Climate History Based on Tree Ring Data

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Year

Avg. Precipitation

(inches)

The southern U.S is the 100th year of a 300 year arid cycle, this is not what we should be calling a drought

Univ. of Arizona – Tree Ring Research Lab

“Results are not predictions, but rather a starting point for dialogue and increased awareness of potential impacts of climate change.”

Roach et al, 2013

Projected Rio Grande Flows through 2100

Traditional Western Surface Water Availability Relies Heavily on Annual Mountain Snowmelt

Illustrative example (Southwest)

Month

60-70 % of western river flows come from runoff of snowmelt in mountain watersheds

Two major contributing factors - forest management and climate

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The Number, Size, and Severity of Forest Fires Has Grown Significantly in the U.S. Over the Last Four Decades

Noted by U of A 2006, and finally by NOAA 2012, NASA 2012, USDA 2012, Harvard 2013, 2013 draft NCA

Forest Management Contributions to Fire Intensity

Many small trees, high intensity fires

Few large trees, low intensity fires

• Past forest and fire management practices have contributed to increased fuel loads and fire severity.

• Future management practices must consider climate change impacts.

(Tree Diameter)

Photo: Craig Allen, USGS

Ecosystem Damage from High Intensity Fires

Watershed, Water Quality, and Reservoir Damage from High Intensity Fires

Possible Future Impact of Forest Fires on Mountain Watersheds

Climate change is compounding already unhealthy forest conditions

“You might get to the point where in some parts of the West, there are no more forests.”

Don Wuebbles, 2013 Draft NCA

Forest Treatments Can Reduce Fire Intensity and Reduce Snowpack and Water Yield Loss

Thinning can reduce snow sublimation by up to 50% (Veatch et al. 2009)

Winter ablation in burned areas reduces snowpack by 50% (Harpold et al. 2013)

Transformational Forest Management Solutions to Improve Water Availability and Ecosystems

Improve fire modeling tools to quantify ecologically and water shed safe forest thinning treatments for individual watersheds

Thinning could generate as much as 100 tons per acre of biomass – volumes compatible with distributed rural energy uses such as gasification

Forest fire fighting and fire damage costs can approach or exceed forest thinning costs