Details

Autor(en) / Beteiligte

• Adams, Kenneth D.
• Sada, Donald W.

Titel

Surface water hydrology and geomorphic characterization of a playa lake system: Implications for monitoring the effects of climate change

Ist Teil von

• Journal of hydrology (Amsterdam), 2014-03, Vol.510, p.92-102

Ort / Verlag

Kidlington: Elsevier B.V

Erscheinungsjahr

2014

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• •Landsat imagery was used to assess the hydrology of the Black Rock Playa.•Lakes periodically appear on the playa due to spring snowmelt.•Lakes range in size up to about 300km2, containing about 100,000,000m3 of water.•Current study establishes baseline hydrologic conditions for this playa system.•Monitoring networks of playas may help hydrologic effects of climate change. Playa lakes are sensitive recorders of subtle climatic perturbations because these ephemeral water bodies respond to the flux of diffuse and channelized flow from their watersheds as well as from direct precipitation. The Black Rock Playa in northwestern Nevada is one of the largest playas in North America and is noted for its extreme flatness, varying less than one meter across a surface area of 310km2. Geo-referenced Landsat imagery was used to map surface-area fluctuations of ephemeral lakes on the playa from 1972 to 2013 to provide baseline data on surface water hydrology of this system to compare to future hydrologic conditions caused by climate change. The area measurements were transformed into depth and volumetric estimates using results of detailed topographic global positioning system (GPS) surveys and correlated with available surface hydrological and meteorological monitoring data. Playa lakes reach their maximum size (<350km2) in spring, fed by melting snows from high mountains on the periphery of the drainage basin, and usually desiccate by early- to mid-summer. The combination of a shallow groundwater table, sediment deposition, and hydro-aeolian planation probably are largely responsible for the flatness of the playa. When lakes do not form for a period of several years, the clay- and silt-rich playa surface transforms from one that is hard and durable into one that is soft and puffy, probably from upward capillary movement of water and resultant evaporation. Subsequent flooding restores the hard and durable surface. The near-global availability of Landsat imagery for the last 41years should allow the documentation of baseline surface hydrologic characteristics for a large number of widely-distributed playa lake systems that can be used to assess the hydrologic effects of future climate changes.