AGRICULTURE-TO-INSTREAM AND URBAN WATER TRANSFERS IN THE CENTRAL VALLEY OF CALIFORNIA: AN ECONOMIC REALITY CHECK

More than two million acre-feet (MAF) of water transfers from agriculture to urban and instream are discussed and debated in California. We use a regional agricultural production and water transfer model to evaluate potential third party impacts of transferring one MAF of water from the Central Valley of California. A range of impacts is estimated under three different scenarios. Our base scenario shows that the adverse economic impacts in the area of origin include a $170 net personal income loss for each acre-foot of water transferred, and 8 job losses for each thousand acre-feet of water transferred.Resource /Energy Economics and Policy,

Analysis of Agricultural Economics for the Central Valley Project Improvement Act Programmatic Environmental Impact Statement

Environmental Economics and Policy,

An Economic Model of Water Transfer Analysis for the Central Valley Project Improvement Act

Resource /Energy Economics and Policy,

Snowmelt-triggered debris flows in seasonal snowpacks

Snowmelt-triggered debris flows commonly occur in mountains. On 14 June 2019, a debris flow occurred on a steep, east-facing slope composed of unconsolidated glacial and periglacial sediments in Yosemite National Park. Originating as a shallow landslide, ~1,300m3 of ripe snow was instantaneously entrained into the debris flow carrying boulders, trees, and soil downslope. The forested area at the toe of the slope strained out debris leaving a muddy slurry to issue across Highway 120 during dewatering. We document this mass movement and assesses its initiation using local snowpack and meteorological data as well as a regional atmospheric reanalysis to examine synoptic conditions. A multiday warming trend and ripening of the snowpack occurred prior to the event as a 500 hPa ridge amplified over western North America leading to record warm 700 hPa temperatures. Anomalous temperatures and cloud cover prevented refreezing of the snowpack and accelerated its ripening with meltwater contributing to soil saturation. Similar conditions occurred during the catastrophic 1983 Slide Mountain debris flow, also hypothesized to be snowmelt initiated. With projected increases in heat waves, our findings can support natural hazard early warning systems in snow-dominated environments

A 50,000-year record of lake-level variations and overflow from Owens Lake, eastern California, USA

A continuous lake-level curve was constructed for Owens Lake, eastern California by integrating lake-core data and shoreline geomorphology with new wind-wave and sediment entrainment modeling of lake-core sedimentology. This effort enabled refinement of the overflow history and development of a better understanding of the effects of regional and global climate variability on lake levels of the paleo-Owens River system during the last 50,000 years. The elevations of stratigraphic sites, plus lake bottom and spillway positions were corrected for vertical tectonic deformation using a differential fault-block model to estimate the absolute hydrologic change of the watershed-lake system. New results include 14C dating of mollusk shells in shoreline deposits, plus post-IR-IRSL dating of a suite of five beach ridges and OSL dating of spillway alluvial and deltaic deposits in deep boreholes. Geotechnical data show the overflow area is an entrenched channel that had erodible sills composed of unconsolidated fluvial-deltaic and alluvial sediment at elevations of ∼1113–1165 m above mean sea level. Owens Lake spilled most of the time at or near minimum sill levels, controlled by a bedrock sill at ∼1113 m. Nine major transgressions at ∼40.0, 38.7, 23.3, 19.3, 15.6, 13.8, 12.8, 11.6, and 10.6 ka reached levels ∼10–45 m above the bedrock sill. Several major regressions at or below the bedrock sill from 36.9 to 28.5 ka, and at ∼17.8, 12.9, and 10.4–8.8 ka indicate little to no overflow during these times. The latest period of overflow occurred ∼10–20 m above the bedrock sill from ∼8.4 to 6.4 ka that was followed by closed basin conditions after ∼6.4 ka. Previous lake core age-depth models were revised by accounting for sediment compaction and using no reservoir correction for open basin conditions, thereby reducing discrepancies between Owens Lake shoreline and lake-core proxy records. The integrated analysis provides a continuous 50 ka lake-level record of hydroclimate variability along the south-central Sierra Nevada that is consistent with other shoreline and speleothem records in the southwestern U.S

AGRICULTURE-TO-INSTREAM AND URBAN WATER TRANSFERS IN THE CENTRAL VALLEY OF CALIFORNIA: AN ECONOMIC REALITY CHECK

More than two million acre-feet (MAF) of water transfers from agriculture to urban and instream are discussed and debated in California. We use a regional agricultural production and water transfer model to evaluate potential third party impacts of transferring one MAF of water from the Central Valley of California. A range of impacts is estimated under three different scenarios. Our base scenario shows that the adverse economic impacts in the area of origin include a $170 net personal income loss for each acre-foot of water transferred, and 8 job losses for each thousand acre-feet of water transferred

Snowmelt-triggered debris flows in seasonal snowpacks

Snowmelt-triggered debris flows commonly occur in mountains. On 14 June 2019, a debris flow occurred on a steep, east-facing slope composed of unconsolidated glacial and periglacial sediments in Yosemite National Park. Originating as a shallow landslide, ~1,300m3 of ripe snow was instantaneously entrained into the debris flow carrying boulders, trees, and soil downslope. The forested area at the toe of the slope strained out debris leaving a muddy slurry to issue across Highway 120 during dewatering. We document this mass movement and assesses its initiation using local snowpack and meteorological data as well as a regional atmospheric reanalysis to examine synoptic conditions. A multiday warming trend and ripening of the snowpack occurred prior to the event as a 500 hPa ridge amplified over western North America leading to record warm 700 hPa temperatures. Anomalous temperatures and cloud cover prevented refreezing of the snowpack and accelerated its ripening with meltwater contributing to soil saturation. Similar conditions occurred during the catastrophic 1983 Slide Mountain debris flow, also hypothesized to be snowmelt initiated. With projected increases in heat waves, our findings can support natural hazard early warning systems in snow-dominated environments