The California Biodiversity Center: understanding the ...



CALIFORNIA BIODIVERSITY CENTER

2002-2003 FISCAL YEAR REPORT

PREPARED BY

MARY E. POWER, DIRECTOR

And

JOHN LATTO, ACADEMIC COORDINATOR

with field station reports from

JEFF BROWN

DIRECTOR, SAGEHEN FIELD STATION

AND

RANDALL OSTERHUBER

CENTRAL SIERRA SNOW LABORATORY

Unit Mission and Activities

The California Biodiversity Center (CBC, ), a new organized research unit, fosters collaborations between the Berkeley Natural History Museums, Berkeley's Natural History Field Stations, and other partners studying changes in California's biological diversity, past, present, and future. Biological populations in California and elsewhere can change unexpectedly with dramatic consequences, both biological and economic. We see an exotic weed, present at low densities for decades following its introduction, suddenly explode as a noxious pest (e.g., yellow star thistle); sudden oak death and other pathogens threaten tanoaks, coast live oaks, madrones, redwoods, and Monterey pines; a native frog population (e.g. mountain yellow legged frog) thriving in one watershed but dwindling or disappearing in another, apparently similar habitat. In all of these cases, ecological change, evolutionary (genetic) change, or both could account for the change in the species' performance and impact. Interactions of genetic and ecological change probably drive many changes in biodiversity and environments, yet such interactions go widely unrecognized because of the lack of collaboration between scientists familiar with museum-based, historical approaches and field ecologists and earth scientists using field observations and experiments to investigate contemporary processes. Such collaborations are fostered by the CBC.

The CBC's affiliated partners include Berkeley's Natural History Museums and Field Stations (Table 1). The field stations provide protected areas that serve as "living laboratories," where researchers can investigate the on-going processes that are currently influencing biological diversity. The museums’ vast collections and databases add geographic breadth and historical depth to our understanding of processes that can control biodiversity--processes that begin with the geologic origin of California and range in time scale from the splitting of species lineages to changes within a single generation. Combining these two invaluable types of resources enhances the abilities of CBC researchers to evaluate the relative roles of climate, evolution, human impacts, and new pathogens in changing distributions, abundances, and genomes of key species over time.

Table 1. Affiliated partners of the California Biodiversity Center

|Berkeley Natural History Museums |Berkeley Natural History Field Stations |

| | |

|University of California Museum of Paleontology |Angelo Coast Range Reserve |

|Museum of Vertebrate Zoology |Hastings Natural History Reservation |

|University of California Botanical Garden |Hans Jenny Pygmy Forest Reserve |

|Essig Museum of Entomology |Chickering-American River Reserve |

|University and Jepson Herbaria |Sagehen Creek Field Station |

|Hearst Museum of Anthropology |Sierra Snow Lab |

CBC Activities, 2002-2003

The CBC organized two retreats in 2003. A Berkeley Natural History Museum Director's Retreat at the Angelo Reserve held from 9-11 May 2003. This included discussion of the development of funding applications and the ongoing research at the reserve. The was also a presentation by George Brimhall (Professor of Geology, Earth Resources Center, UCB). The presentation covered digital paperless mapping research to facilitate hypothesis generation and testing in field sciences--adapting GeoMap to EcoMap or PhylogeoMap—links with digital identification guides etc. This was followed by a field demonstration of technology applied to Angelo Reserve. The CBC also sponsored a new graduate student retreat at the Angelo Coast Range Reserve to welcome and orient new graduate students in the Department of Integrative Biology at Berkeley in August, 2003.

The CBC helped organize and provided logistical support for an NSF Planning Workshop held at The Angelo Reserve from 4-7 September 2003. The participants included twelve scientists from outside the University of California, seven faculty from three departments at UCB (one of whom was the campus Vice Chancellor for Research, and another the Director of the UC Systemwide NRS ) a Science Writer from the UC Natural Reserve System and the Director of the Hastings Natural History Reservation (also in the NRS. Following a general orientation to the site, guided field trips demonstrating ongoing research projects, and a day and a half of discussion, the review committee reached several recommendations for future research directions at the reserve and identified critical priorities for improvements to facilities and infrastructure.

On February 3 2003 CBC arranged an Ecoinformatics Workshop follow-up. This built upon the Ecoinformatics Workshop held in 2002. Four scientists currently working in this area gave brief overviews of their work and the tools they are using to the weekly Ecolunch seminar series on campus. Presentations were made by Mark Stromberg (Reserve Manager at Hastings Natural History Reservation), John Battles (Associate Professor Division of Ecosystem Science), Neo Martinez (Assistant Professor of Biology at the Romberg Tiburon Center of San Francisco State) University and Rich Williams (postdoctoral researcher, San Francisco State University)

In April 2003 CBC provided funds to supplement research awards to four undergraduates to carry out research projects that use both museums and field sites, and combine evolutionary, systematic, biogeographical, and ecological biology. These research projects were all carried out in collaboration with faculty at UC Berkeley.

John Latto, Peter and Trish Steel and Mary Power, initiated a collaboration with Education Outreach staff of the National Center for Earth Surface Dynamics (NCED) to develop high school exchanges and school outreach programs. These would train students as docents at the field reserves by giving them Initial summer employment as field assistants at reserves. The program will also bring students to NCED labs and field sites in Minnesota and Minnesota students to the Angelo Reserve. The program will have a special emphasis on Native Americans within both communities. Trish Steel, tsteel@, Laytonville Coordinator North Coast Rural Challenge Network will participate in Oct. 5-10 NCED workshop, and continue developing these collaborative outreach efforts on behalf of Angelo Reserve and Laytonville schools.

Over the whole of the 2003-2003 year CBC has sponsored the production of weekly seminar listing for all ecology, environmental science and evolution related seminars on campus. (See ). This listing has become widely used by ecologists and environmental scientists in many different departments on campus.

In May 2003 CBC Director Mary Power was a speaker at the System-Wide Committee Meeting of the U.C. Natural Reserve System, Oakland CA. In June 2003 she gave a presentation for the NSF Site Review of the National Center for Earth Surface Dynamics, Minneapolis, MN. Angelo is used as a primary field site for this NSF STC.

Field Station Activities, 2002-2003

Angelo Coast Range Reserve: 2003 Annual Report

About the reserve:

The Angelo Coast Range Reserve (ACRR) is one of 34 reserves protected for university level teaching and research by the University of California Natural Reserve System (UCNRS, ). The Angelo Reserve is administered by the Berkeley campus through the California Biodiversity Center. The reserve was established in 1959 by the Nature Conservancy (TNC) and Heath and Marjorie Angelo, and was managed by TNC until 1989 when management was turned over to the UCNRS. Title to the reserve was transferred in 1994. In 1961 the Bureau of Land Management (BLM) set aside some of its adjacent land in recognition of its natural value. Together the two areas combine to form an 8000 acre natural area for research, teaching, and public environmental education.

The reserve is located in northern Mendocino Co. in the steep and rugged Coast Range. Elevations range from 390 m to 1263 m. Habitats include mixed evergreen forest, chaparral, oak woodlands, meadows, and riparian zones along the S. Fork Eel River. In addition to a 5-km reach of the S. Fork Eel River, the reserve encompasses the entire watersheds of 3 perennial streams. The climate is typically Mediterranean, with the bulk of the rain falling between November and March, followed by long dry and warm summers.

Collections on site include an extensive herbarium and plant species list, as well as surveys of mammals, soils, fish, birds, reptiles and amphibians. The USGS has maintained a gauging station on Elder Creek since 1974.

Angelo Reserve Facilities support year round research and teaching, and include individual as well as group housing available to any qualified person, institution, or group, on a per/person/night basis. When fully furnished the newly completed Environmental Science Center (funded by a grant from the Goldman Foundation) will provide lab space, computer lab, library and collections room, class/conference room, and high-speed internet connection. Recent users include graduate students and classes from UC Berkeley, UC Davis, UC Santa Cruz, Humboldt State University, SF State University, classes from College of the Redwoods, K-12 classes from the Laytonville Unified School District and local private schools, USGS, Cal. Fish and Game, and over 1500 public day users.

The Angelo Coast Range Reserve will serve as a primary field laboratory for a new NSF Science and Technology Center, the National Center for Earth Surface Dynamics (NCED). In September 2002 Earth scientists, ecologists, engineers, and educators from U.C. Berkeley, the Massachusetts Institute of Technology, the University of Minnesota, and Fond du Lac College in northern Minnesota met at the new Environmental Center recently completed at the Angelo Reserve. Focused discussions with the entire core NCED team, as well as breakout group discussions, were held to map out several research areas and particular collaborations. Two such projects, an examination of ecosystem physiology over scales from microns to kilometers, and a study of how riparian trees influence the evolution of channel morphology, were launched at the Angelo Reserve in summer 2003 (collaborating PIs Hondzo and Finlay from U. Minn and Power from UCB) and will continue over the coming field seasons. NCED will fund high speed internet connections to the Angelo Reserve, which will serve as a primary field laboratory for this Minneapolis-based NCED ().

Selected 2002-2003 Research Projects are described in Appendix 2.

Sagehen Creek Field Station: 2003 Annual Report

Description

Sagehen Creek Field Station(SCFS) is a research and teaching facility of the University of California at Berkeley's, Office of the Vice Chancellor for Research, the Berkeley Natural History Museums and the California Biodiversity Center. The Station was established in 1951 with the signing of a long-term special use permit with the USDA Forest Service, which

manages the land.The year round Station facilities are at an elevation of 6380 feet in California on the east slope of the northern Sierra Nevada, approximately 20 miles North of Lake Tahoe. The roughly 8000 acre Sagehen Creek watershed includes yellow pine, mixed conifer, and red fir forests, brushfields, scattered mountain meadows and fens. Deep snow is typical of the winter season, and dry, warm weather is typical of the summer period. Sagehen Creek is about 8 miles long, extending eastward from near the crest of the Sierra to Stampede Reservoir on the Little Truckee River. The watershed is managed by the Truckee Ranger District of the Tahoe National Forest for multiple uses. Sagehen Creek is a candidate for inclusion in the Wild and Scenic River Inventory and the UC Natural Reserve System.

Station Manager Jeffrey R. Brown

Address University of California, Berkeley

Sagehen Creek Field Station

P.O. Box 939, 11616 Sagehen Rd, Truckee, CA 96160

Telephone (530) 587-4830

Fax (530) 582-4031

Email SagehenC@uclink.berkeley.edu

Web Site

Established 1951

Multicampus Research / Public Outreach

SCFS provides full service, multidisciplinary research and classroom facilities to any qualified group on a per night/per person use fee basis. Use of the station and facilities is quite varied and applications/reservations are accomplished through an online system. Recent use includes: UC Berkeley graduate students and classes, UC Davis graduate students and classes, SFSU graduate students, the USDA Forest Service, California Fish & Game, University of Nevada at Reno, the Desert Research Institute, The Truckee School District, Truckee River Watershed Council, USGS, Lawrence Hall of Science, The Nature Conservancy, California Public

Health Service, Lawrence Livermore National Lab, UC Irvine, UC Riverside, University of Chicago Field Museum, UC Santa Cruz Herbarium, UC Santa Barbara and California Partners in Flight.

Sagehen Creek is a Benchmark Creek for the USGS and water samples have been

collected and analyzed since 1975. Weather data has been collected since

the early 1950's. Stream flow measurements and temperatures have been taken

at the USGS stream gauging station on Sagehen Creek since the early 1950's.

Extensive plant, mammal, vegetation, fish, soils, archaeologic and insect

survey records are on file. Over 75 PHD and Masters theses and more than

300 other scientific publications have been produced from research efforts

conducted at SCFS. Data sets and plant/mammal/bird/insect lists are available online through the station’s website.

A wireless network, 3 additional automated weather stations and a full service GIS Center were installed in 2003 and renovation has begun for several buildings within the reserve.

SCFS has an underwater observation building built adjacent to Sagehen

Creek. This facility has 3-8' long underwater viewing windows that enable

various projects relating to streams to be conducted.

Central Sierra Snow Laboratory: 2003 Annual Report

Administered by the California Biodiversity Center

by Randall Osterhuber

Manager and Staff Research Associate

Central Sierra Snow Laboratory

PO Box 810

10162 Bunny Hill Road

Soda Springs, California 95728 USA

(530) 426-0318

(530) 426-0319 fax

email contact: randall@





wrcc.dri.edu/weather/cssl.html

The Central Sierra Snow Laboratory (CSSL)

Since its inception in 1946 (built by the then U.S. Weather Bureau and Army Corps of Engineers), the CSSL has been a snow hydrology research facility. The Central Sierra Snow Laboratory is a research field station of UC Berkeley specializing in snow physics, snow hydrology, meteorology, climatology, and instrument design.

The CSSL's mission is to provide a facility for research to address the uncertainties, characteristics, and timing of the Sierra Nevada's snowfall and hydrologic cycle. This includes, but is not limited to, the temporal and spatial distribution of the accumulating and ablating snowpack; the snowpack's physical and chemical response to atmospheric and anthropogenic phenomena; and identifying short and long term implications of these phenomena to snowpack ground- and surface-water yield. Since more than 50 percent of California's usable fresh water is born of the melting Sierra Nevada snowpack, understanding the physical variations of snowpacks and alpine watershed climatic regimes is essential if water managers are to have sufficient resiliency to cope with climatic change. Industry, recreation, riparian health, recreation, and domestic water use all have claims—and sometimes competing interests—levied against the snow zone's water yield.

Current research activities at the CSSL (Appendix 3) include using rare earth elements as solute transport tracers within the snowpack; measuring the attenuation of cosmic radiation through snow to assess snowpack snow water equivalent; trends in climatology and snowpack characteristics during the past 13 decades; weather instrument testing and evaluation; avalanche safety and forecasting; and conducting various community education and outreach programs that address local snow hydrology and weather issues.

Personnel

Andrew Barkhuff, Program Manager, National Weather Service 6,7

Mark Bollinger, Research Scientist, 2B Technologies 4

Elizabeth Carter, Atmospheric Scientist, Firnspiegel 5,6

David Collins, Electrical Engineer, Dartmouth College 3

Ken Condreva, Research Scientist, Sandia National Laboratories 4

Michael Dettinger, USGS, Scripps Institution of Oceanography 6,7

Anthony Faaia, Dartmouth College 3

Xiahong Feng, Professor of Geophysics, Dartmouth College 3

Frank Gehrke, Chief, Snow Surveys, CA Department of Water Resources 4,6,7

Emma Goldberg, UC Berkeley 2

Dan Greenlee, Hydrologist, USDA-Natural Resource Conservation Service 6,7

Kathy Hoxsie, Meteorologist, National Weather Service 6

Arlen Huggins, Research Climatologist, Desert Research Institute 6

Richard Kattelmann, Snow Hydrologist, UC Santa Barbara 5

James Kirchner, Professor of Geophysics, UC Berkeley 1,3

Björn Klaue, Hydrologist, Department of Geological Sciences, University of Michigan 3

Joyce Leighton, Administrative Analyst 1

Jessica Lundquist, Scripps Institution of Oceanography, UC San Diego 1,4,6

Greg McCurdy, Programmer, Desert Research Institute 6

Bob Moore, Snow Ranger, Tahoe National Forest 5

Gary Murphy, Avalanche Forecaster, Alpine Meadows Ski Corp 5

Randall Osterhuber, Research Associate, Central Sierra Snow Laboratory 1,3,4,5,6,7

Kelly Redmond, Climatologist, Desert Research Institute 6

Carl Renshaw, Geophysicist, Department of Earth Science, Dartmouth College 3

Tarel Selles, Analyst 1

Dave Simeral, Desert Research Institute 6

Alex Tardy, Meteorologist, National Weather Service 6

Susan Taylor, Hydrologist, US Army Cold Regions Research and Engineering Laboratory,

Hanover, NH 2,3

Bill Williamson, Operations Director, Sugar Bowl Ski Area 5

1 UCB Faculty/Staff

2 Student

3 REE project

4 Gamma sensor project

5 Avalanche safety/forecasting

6 Meteorology/Climatology/Monitoring

7 River flow forecast

Appendix 1. Attendees at NSF Planning Workshop, Angelo Coast Range Reserve, September 4-7, 2003

|Cherie Briggs |Jim Kirchner |

|Associate Professor, Department of Integrative Biology, |Professor, Department of Earth and Planetary Science |

|University of California, Berkeley |E-mail: kirchner@seismo.berkeley.edu |

|E-mail: cbriggs@socrates.berkeley.edu |Tom Lisle |

|Jerry Booth |Research Hydrologist, USDA-USFS Redwood Sciences Laboratory, |

|Senior Science Writer, University of California Natural Reserve |Arcata, CA |

|System |E-mail: tel7001@axe.humboldt.edu |

|E-mail: jerry.booth@ucop.edu |Carolyn B. Meyer |

|Mary Beth Burnside |Lecturer, Department of Botany, University of Wyoming |

|Vice Chancellor for Research and Chancellor's Professor of Cell &|E-mail: meyerc@uwyo.edu |

|Developmental Biology |Michael Parker |

|E-mail: burnside@socrates.berkeley.edu |Associate Professor in the Department of Biology, Southern Oregon|

|Todd Dawson |University |

|Associate Professor in Integrative Biology at the University of |E-mail: parker@sou.edu |

|California Berkeley |Mary Power |

|E-mail: tdawson@socrates.berkeley.edu |Professor, Department of Integrative Biology, University of |

|Bill E. Dietrich |California, Berkeley |

|Professor, Earth and Planetary Sciences, at the University of |E-mail: mepower@socrates.berkeley.edu |

|California |John Schade |

|E-mail: bill@geomorph.berkeley.edu |Postdoc at Arizona State University |

|Alexander Glazer |E-mail: john.schade@asu.edu |

|Professor of the Graduate School of Biochemistry & Molecular |Art Stewart |

|Biology at the University of California Berkeley. Director, UC |Environmental Sciences Division, Oak Ridge National Laboratory |

|Natural Reserve System. |E-mail: Zcatfish12@ |

|E-mail: glazer@uclink4.berkeley.edu |David L. Strayer |

|Robert O. Hall, Jr. |Aquatic Ecologist, Institute of Ecosystem Studies Millbrook NY |

|Assistant Professor, Dept. of Zoology and Physiology, University |E-mail: strayerd@ |

|of Wyoming |Mark Stromberg |

|E-mail: bhall@uwyo.edu |Resident Reserve Director, Hastings Natural History Reservation |

|Bret C. Harvey |E-mail: stromberg@ |

|Research Fisheries Biologist, USDA-USFS Redwood Sciences |Jill Welter |

|Laboratory, Arcata, CA |PhD Candidate, School of Life Sciences, Arizona State University |

|E-mail: bch3@axe.humboldt.edu |E-mail: jill.welter@asu.edu |

|John Hunter |David Wise |

|Plant Ecologist |Professor of Entomology, University of Kentucky |

|JHunter@ |E-mail: dhwise@uky.edu |

|Carol Kendall | |

|Chief of the Isotope Tracers Project, USGS Menlo Park Stable | |

|Isotope and Tritium Labs. | |

|E-mail: ckendall@ | |

| | |

Appendix 2. Selected Research Projects at the Angelo Coast Range Reserve 2002-2003

Spatial scales in river and watershed food webs. Isotopic tracers, increasingly available, reveal flow paths through space and time of organisms or their elemental constituents. Concurrently, new mapping technologies based on remote sensing are being developed to characterize landscape features (e.g. watershed divides, thermal cells in oceans) that contain and constrain these fluxes and the food webs they support. At the Angelo reserve, both of these tools support studies of how cross-habitat fluxes from rivers to forests affect consumers, communities, and ecosystems in recipient watershed habitats (Power and Rainey 2000). Subsidies (exported algae and emergent aquatic insects) and boundaries have been experimentally manipulated to study their effects on terrestrial consumers, food webs and ecosystems (e.g., Sabo and Power 2002). New work with scientists, engineers, and modelers at the National Center for Earth Surface Dynamics should permit upscaling and increased understanding of how these ecological processes contribute or respond to more regional dynamics. Profs. Miki Hondzo and Jacques Finlay (U. Minnesota) brought 3 graduate students and one undergraduate to collaborate with Mary Power and her graduate students and postdocs on a measurement of stream ecosystem metabolism (community respiration and community photosynthesis) in eight watersheds within the South Fork Eel drainage network that vary in area from about 1 to about 260 sq. km. These measurements will provide a quantitative foundation for studies of the distributions, performances and interactions of key organisms in these channel habitats. They will underlie future planned examination of the responses of their communities to alterations in productivity or disturbance regimes imposed by natural year to year variation (e.g. climate change) or land use.

Otolith and isotopic analysis of habitat use by juvenile salmonids in a river drainage network. Following up on work by Jacques Finlay and others at the Angelo Reserve (Finlay et al. 2002), Dr. Peter Weber (Geography, UCB) wanted to determine if the carbon isotope patterns seen in river and stream food webs were reflected in the otoliths of the fish. Otoliths are banded calcium carbonate accretions in the inner ear of bony fish. They grow continuously over the life of the fish and, unlike bone, are metabolically inert. Therefore, these structures contain a chemical history of the fish. Otolith carbon isotopic composition could potentially be used to reconstruct the feeding and geographic history of a fish. Aquatic food web carbon isotopes are complex and therefore the opportunity to follow up on previous carbon isotope work at the Angelo Reserve was welcome. Otoliths and insect samples were collected. The analyses are in process.

Impacts of fine deposited sediment on juvenile salmonids and the food webs that support them. Excessive loading of fine sediments into western rivers has degraded spawning and rearing habitat for salmonids, and contributed substantially to their declines. Impacts on salmon redds have been studied extensively, but effects on juvenile rearing are less well documented. A field experiment in the South Fork Eel River examined the impacts of deposited fine sediment on juvenile steelhead with a design that allowed the effects of fine bed sediments to be isolated from other covarying factors. Increasing levels of embeddedness with deposited fine sediment (from zero to 100%) decreased growth and survival of juvenile steelhead trout. The nearly linear decreases in growth resulted from decreased food availability and metabolic costs of increased activity and intraspecific aggression. The invertebrate community changed from one of more available prey to one of unavailable burrowing taxa with higher levels of deposited fine sediment. Steelhead in more heavily embedded channels showed more continuous movement and aggression and higher incidence of injury. This study (Power et al. 2002, Suttle et al., in press) shows a direct impact of riverbed composition on salmonid rearing success, which has been identified as a life history bottleneck in models informing efforts to recover these populations.

In continuing research on the impacts of deposited fine sediment in river food webs (Power et al. 2002, Suttle et al., in press), Blake Suttle (graduate student, Integrative Biology) explored how fine bed sediment concentration affects interactions between mayfly larvae, the most abundant aquatic grazers, and dragonfly and damselfly larvae, their major invertebrate predators. He measured predation on mayfly grazers in replicate enclosures of differing bed compositions and found that increasing levels of deposited fine sediment lead to greater predation, indicating that high levels of deposited fine sediment simplify and perhaps shorten river food webs.

Rebecca Doubledee investigated the distribution, abundance, and activity levels of Rana boylii, a native frog species of special concern, with respect to the concentration of fine deposited bed sediment.

Influence of mutualistic ant-aphid interactions on an invasive riparian plant. Will Sattherthwaite, a Ph.D. candidate at UCSC, investigated effects of the interactions of ants and aphids on invasive European thistles along the active river channel.

Effects of predators on plants transmitted through pollinators. With undergraduate Mary Sorenson, Blake Suttle examined the effect of a predator of pollinating insects on the reproductive success of the invasive plant from which it hunts. They found strong negative indirect effects of the predator (crab spiders) on the plant (ox-eyed daisies), indicating that this predator may limit the invasive spread of this plant, a previously undocumented form of biotic resistance to invasion. This research produced the cover article for a 2003 Ecology Letters volume.

Simulated climate change in an annual grassland. Blake Suttle completed the second year of a four-year manipulation of the duration and intensity of rainfall in large grassland plots, as forecast for Northern California under two leading climate change models, to generate predictions for the fate of these grasslands under alternate climate change scenarios. Plant related response variables include seasonal cover, biomass, and decomposition rate of each major plant group, disturbance recolonization, nitrogen availability (as both labile soil N and grass leaf tissue N), and species richness. Animal related response variables include richness and abundance of taxa, as measured through seasonal sweep net and pitfall samples. He also conducted two field experiments and extensive grasshopper foraging behavior observations examining how changes in resource availability, herbivory, and predation affect food chain structure in northern California annual grasslands.

Meredith Wilson in Carla D'Antonio’s lab in Integrative Biology, continued ongoing field research examining the responses of native grasses to alternate climate change scenarios predicted by leading climate models. In replicate plots in Blake Suttle’s experiment receiving different amounts and duration of precipitation, three native grass species were added as seed, plugs, and large tussocks. Plugs of the European perennial grass, Holcus, were also introduced and monitored. The survival, growth, and reproductive success of each is being monitored for three years.

Appendix 3: Current Research Activities and Recent Publications from the University of California Berkeley Central Sierra Snow Laboratory

Current Research Activities

Snowpack Solute Transport Mechanisms

Snowmelt often accounts for the majority of the annual water input to a catchment. During the winter, snowpacks accumulate and store atmospherically deposited chemical contaminants. But the chemical composition of snowmelt does not equal the average composition in the snowpack itself, but varies temporally as melting proceeds. During snow metamorphism, solutes tend to be concentrated near the exterior of snow grains, resulting in an ionic pulse during the first ~25 percent of snowmelt. The magnitude of this ionic pulse is dependent upon the solute transport mechanism. At the CSSL, very dilute concentrations of rare Earth elements (REE) are applied to the snow surface at intervals throughout the winter. These REEs act as tracers, the presence of which are detected in the snowpack meltwater. Observations of the travel time, distance, and concentration of each REE can distinguish between piston and preferential flow. Distinguishing between these two transport mechanisms may have important implications for solute transport processes at the watershed level.

Assessing Total Snowpack Snow Water Equivalent by the Attenuation of Deep-Space Radiation

Remote sensing of snowpack snow water equivalent (swe) is most commonly measured with large (7.5 m2) bladders filled with an antifreeze fluid. The fluid is compressed by the weight of the overlaying snowcover and the subsequent pressure on the antifreeze is measured by a pressure transducer or manometer. There are many problems with this technique of attempting to "weigh" a finite column of snow cover that is somewhat infinite in extent. These problems include bridging of the sensor, flooding, plumbing leaks, and siting and installation difficulties. New swe sensing techniques are under development at the CSSL that measure the slight attenuation of very high energy gamma radiation as it passes through the snowpack. This radiation originates in deep space and is quite constant at any one location on Earth. A small cube (~8 cm3) of scintillating material records the gamma energy, one cube placed at ground level, another stationary above the snowpack. The energy spectra of the two are compared, and it is found that the attenuation is exponentially related to the snowpack swe. These sensors are small, portable, and solid-state. Refinements of design and application are ongoing at the CSSL.

Avalanche Safety and Forecasting

The avalanche fatality rate in the western US continues to climb; the lead demographic among winter recreationists being snowmobilers. The fatality rate in the Sierra Nevada, despite its prolific snowfall and high concentration of winter recreationists, is a small fraction of Colorado, Wyoming, Utah, and Montana. This is largely due to the snowpack-stabilizing effect of (relatively) warmer winter air temperatures common throughout the Sierra Nevada. Nevertheless, the Sierra is averaging about one avalanche fatality per winter. Data (air temp, snowfall, snowpack settlement, wind speed/direction, precipitation) from the CSSL is used to generate daily avalanche hazard forecasts from mid-November through April. These forecasts are distributed on the internet via private and government sites. Research at the CSSL also concentrates on the identification of potential shear layers within the snowpack and the mechanisms that promote their formation and disappearance. Interviews are also conducted with individual winter recreationists regarding their avalanche and backcountry experience. One goal is to explain why a large increase in the number of women winter recreationists does not positively correlate with the almost exclusively male-dominated avalanche accident/fatality demographic.

Long-Term Meteorological and Climatological Trends, Measurements, and Monitoring

The CSSL has fairly complete meteorological records dating from 1946 (when the CSSL was built). There have been meteorological measurements recorded on Donner Summit immediately surrounding the CSSL since 1870. The Southern Pacific Railroad, Pacific Gas and Electric, and the California Department of Water Resources are responsible for the early data collection. Combined, the data stream is 132 years. No other data stream of such length from a high-elevation western snow zone exists. Investigations of periodicity, recurrence intervals, climatic extremes, and trends within the historic record are ongoing. The CSSL is a reporting met station: part of the newly-formed trans-Sierra climate monitoring program. Much of the data collected at the CSSL is displayed on-line; more instruments being added all the time. Data from the CSSL is used and archived by hundreds of agencies and individual users.

Community Outreach

The CSSL conducts many tours of its facility and research projects each winter. Visiting groups range from hydrology graduate classes to local school groups and interested individuals. In addition, CSSL personnel conduct informative lectures and slide shows on topics of snow and snow hydrology.

Relevant Publications

A Study of Solute Transport Mechanisms Using REE Tracers and Artificial Rain Storms on Snow, Water Resources Research, 37, p. 1425-1435, 2001. Feng, X., Kirchner, J., Renshaw, C., Osterhuber, R., Klaue, B., Taylor, S.

Climate Summary of Donner Summit, 1870 - 2001, Publication of the Central Sierra Snow Laboratory, 2001. Osterhuber, R.

Investigating Periodicity in the Long Term Precipitation Record of Donner Summit, California, Proceedings of the Western Snow Conference p. 92-94, 2000. Osterhuber, R.

Isotopic Evolution of Snowmelt: I. A Physically based 1-D Model, Water Resources Research in press, 2002. Feng, X., Taylor, S., Renshaw, C., Kirchner, J.

Isotopic Evolution of Snowmelt: II. Verification and Parameterization of a 1-D Model Using Laboratory Experiments, Water Resources Research, in press, 2002. Taylor, S., Feng, X., Renshaw, C., Kirchner, J.

Isotopic Evolution of a Seasonal Snowpack and its Melt, Water Resources Research 37, p. 759-769, 2001. Taylor, S., Feng, X., Kirchner, J., Osterhuber, R., Klaue, B., Renshaw, C.

Rare Earth Elements as Chemical Tracers in Snow Studies, Proceedings of the Eastern Snow Conference, p.13-20, 1998. Taylor, S., Feng, X., Klaue, B., Albert, M., Kirchner, J.

Snowpack Snow Water Equivalent Measurement Using the Attenuation of Cosmic Gamma Radiation, Proceedings of the Western Snow Conference, p. 19-25, 1998. Osterhuber, R., Gehrke, F., Condreva, K.

Warm Storms Associated With Avalanche Hazard in the Sierra Nevada, Proceedings of the International Snow Science Workshop, p. 526-533, 1998. Osterhuber, R., Kattelmann, R.

Water Conditions in California, Bulletin 120, California Department of Water Resources, 2002. Gehrke, F. et al.

................
................

In order to avoid copyright disputes, this page is only a partial summary.

Google Online Preview   Download