David Wahl
David is a research scientist at the Geology, Minerals, Energy, and Geophysics Science Center. He received a PhD in Geography from UC Berkeley in 2005. Since joining the USGS in 2004, he has worked to understand drivers and impacts of Quaternary environmental change in North America. Now, his research focuses on reconstructing climate and anthropogenic environmental change.
Biography
After coming to the Menlo Park office of GMEG In 2004, David is currently focused on reconstructing climate and anthropogenic environmental change in the western US, Guatemala, and the central Pacific.
Professional Experience:
- 2004 - Present, Research Geographer, US Geological Survey, Menlo Park, CA
- 2011 - Present, Assistant Adjunct Professor, Geography Department, UC Berkeley
Education:
- Ph.D., Geography, University of California, Berkeley, 2005
- M.A., Geography, University of California, Berkeley, 2000
- B.A., History, Cal Poly, San Luis Obispo, 1996
Science and Products
Drivers and Impacts of North Pacific Climate Variability
Climate model forecasts indicate an increase in extreme hydrologic events, including floods and droughts, for California and the western U.S. in the future. To better understand what the consequences of this future change in climate may be, USGS scientists are studying the frequency, magnitude, and impacts of past hydroclimate variability and extremes in the region. This project produces well-...
Linking modern pollen accumulation rates to biomass: Quantitative vegetation reconstruction in the western Klamath Mountains, NW California, USA
Quantitative reconstructions of vegetation abundance from sediment-derived pollen systems provide unique insights into past ecological conditions. Recently, the use of pollen accumulation rates (PAR, grains cm−2 year−1) has shown promise as a bioproxy for plant abundance. However, successfully reconstructing region-specific vegetation dynamics...
Knight, Clarke A.; Baskaran, Mark; Bunting, M. Jane; Champagne, Marie Rhondelle; Potts, Matthew D.; Wahl, David; Wanket, James; Battles, John J.Holocene paleoclimate change in the western US: The importance of chronology in discerning patterns and drivers
Sediment in lakes and meadows forms a powerful archive that can be used to reconstruct environmental change through time. Reconstructions of lake level, of chemical, biological, and hydrological conditions, and of surrounding vegetation provide detailed information about past climate conditions, both locally and regionally. Indeed, most of our...
Zimmerman, Susan; Wahl, DavidUnderstanding rates of change: A case study using fossil pollen records from California to assess the potential for and challenges to a regional data synthesis
Abstract: Insights into the rates at which ecosystems and vegetation respond to a changing climate is fundamental to anticipating impacts of projected climate change. Characterization of vegetation change over millennia to centuries has potential to make an important contribution toward this goal, and regional scale syntheses of fossil pollen data...
Anderson, Lysanna; Wahl, David; Bhattacharya, T.Radiocarbon and geologic evidence reveal Ilopango volcano as source of the colossal 'mystery' eruption of 539/40 CE
Ilopango volcano (El Salvador) erupted violently during the Maya Classic Period (250–900 CE) in a densely-populated and intensively-cultivated region of the southern Maya realm, causing regional abandonment of an area covering more than 20,000 km2. However, neither the regional nor global impacts of the Tierra Blanca Joven (TBJ) eruption in...
Dull, Robert A.; Southon, John R.; Kutterolf, Steffen; Anchukaitis, Kevin J.; Freundt, Armin; Wahl, David; Sheets, Payson; Amaroli, Paul; Hernandez, Walter; Weimann, Micheal C.; Oppenheimer, ClivePaleoenvironmental, epigraphic, and archaeological evidence of total warfare among the Classic Maya
Despite over a century of archaeological research, the nature and broader consequences of Classic Maya warfare remain poorly understood. Based on frequent epigraphic references and iconographic themes, Classic period (250-950 CE) Maya warfare has largely been viewed as ritualized and limited in scope. Evidence of warfare in the Terminal Classic...
Wahl, David; Anderson, Lysanna; Estrada-Belli, Francisco; Tokovinine, AlexandreA North American Hydroclimate Synthesis (NAHS) of the Common Era
This study presents a synthesis of century-scale hydroclimate variations in North America for the Common Era (last 2000 years) using new age models of previously published multiple proxy-based paleoclimate data. This North American Hydroclimate Synthesis (NAHS) examines regional hydroclimate patterns and related environmental indicators,...
Rodysill, Jessica R. ; Anderson, Lesleigh; Cronin, Thomas M.; Jones, Miriam C.; Thompson, Robert S.; Wahl, David B.; Willard, Debra A.; Addison, Jason A.; Alder, Jay R.; Anderson, Katherine H.; Anderson, Lysanna; Barron, John A.; Bernhardt, Christopher E.; Hostetler, Steven W.; Kehrwald, Natalie M.; Khan, Nicole; Richey, Julie N.; Starratt, Scott W.; Strickland, Laura E.; Toomey, Michael; Treat, Claire C.; Wingard, G. LynnHolocene climate variability and anthropogenic impacts from Lago Paixban, a perennial wetland in Peten, Guatemala
Analyses of an ~ 6 m sediment core from Lago Paixban in Peten, Guatemala, document the complex evolution of a perennial wetland over the last 10,300 years. The basal sediment is comprised of alluvial/colluvial fill deposited in the early Holocene. The absence of pollen and gastropods in the basal sediments suggests intermittently dry conditions...
Wahl, David B.; Hansen, Richard D.; Byrne, Roger; Anderson, Lysanna; Schreiner, T.Two Holocene paleofire records from Peten, Guatemala: Implications for natural fire regime and prehispanic Maya land use
Although fire was arguably the primary tool used by the Maya to alter the landscape and extract resources, little attention has been paid to biomass burning in paleoenvironmental reconstructions from the Maya lowlands. Here we report two new well-dated, high-resolution records of biomass burning based on analysis of macroscopic fossil charcoal...
Anderson, Lysanna; Wahl, David B.Holocene environmental changes inferred from biological and sedimentological proxies in a high elevation Great Basin lake in the northern Ruby Mountains, Nevada, USA
Multi-proxy analyses were conducted on a sediment core from Favre Lake, a high elevation cirque lake in the northern Ruby Mountains, Nevada, and provide a ca. 7600 year record of local and regional environmental change. Data indicate that lake levels were lower from 7600-5750 cal yr BP, when local climate was warmer and/or drier than today....
Wahl, David B.; Starratt, Scott W.; Anderson, Lysanna; Kusler, Jennifer E.; Fuller, Christopher C.; Addison, Jason A.; Wan, ElmiraLimiting age for the Provo shoreline of Lake Bonneville
Pluvial Lake Bonneville features a prominent shoreline at the Provo level, which has been interpreted as having formed during a period of threshold-stabilized overflow. The timing of Provo shoreline development is important for paleoclimate interpretations and for inferences on geomorphic process rates. Estimates for the timing of the shoreline...
Miller, David M.; Wahl, David B.; McGeehin, John; Rosario, Jose J.; Oviatt, Charles G.; Anderson, Lysanna; Presnetsova, Liubov S.A 3400 year paleolimnological record of prehispanic human–environment interactions in the Holmul region of the southern Maya lowlands
The timing, magnitude and drivers of late Holocene environmental change in the Holmul region of the southern Maya lowlands are examined by combining paleoenvironmental and archeological data. Environmental proxy analyses on a ~ 3350 cal yr lacustrine sediment record include pollen, charcoal, loss on ignition, magnetic suscep- tibility, and...
Wahl, David B.; Estrada-Belli, Francisco; Anderson, LysannaAn 8700 year paleoclimate reconstruction from the southern Maya lowlands
Analysis of a sediment core from Lago Puerto Arturo, a closed basin lake in northern Peten, Guatemala, has provided an ∼8700 cal year record of climate change and human activity in the southern Maya lowlands. Stable isotope, magnetic susceptibility, and pollen analyses were used to reconstruct environmental change in the region....
Wahl, David B.; Byrne, Roger; Anderson, LysannaPre-USGS Publications
Sediment cores provide evidence of total warfare among the Classic Maya
This article is part of the Spring 2020 issue of the Earth Science Matters Newsletter.
A 7,600-year record of climate and vegetation change from the northern Ruby Mountains, Nevada, USA
This article is part of the Fall 2015 issue of the Earth Science Matters Newsletter.