Jeff Welker’s US Network for Isotopes in Precipitation (USNIP) was featured in a presentation at the famous Goldschimdt (http://goldschmidt.info/2013/index) international conference this past week in Florence, Italy. The presentation occurred in the session titled: “Reconstructing Terrestrial Hydrology: Proxies, Mechanisms, and Records”. The title of the study was “Variations in Triple Oxygen Isotopes in Precipitation and River Waters in the Continental U.S.”: N Levin, S Li, R Brooks and JM Welker. Naomi Levin (Assistant Professor at John Hopkins University) was the presenter while the PhD student, Shuning Li and EPA Scientist Renee Brooks were contributors and participants.
- Ph.D. Department of Rangeland Ecology and Management, Texas A&M, University, College Station, TX, 1985. Carbon and nitrogen cycling in native bunchgrass plants.
- M.S. Range Science, Range and Animal Science Department, Montana State University, Bozeman, MT,1982. Climate change affects on prairie vegetation.
- B.S. Agriculture-Range Science Major, Range and Animal Science Department, Montana State University, Bozeman, MT, 1980.
The Welker lab is dedicated to understanding the ecophysiological processes governing the functional and structural traits of Arctic/Alpine tundra, boreal forests and temperate grasslands under current and future conditions. Welker’s research program centers on four main themes:
- Experimental and observational studies that examine how carbon and nitrogen cycling in Low and High Arctic ecosystems respond to deeper snow in winter and warmer temperatures in summer;
- Continental-scale processes and patterns of the isotope geochemistry of precipitation as a means to understand the ecohydrology of landscapes and the recording of climate records in proxies such as ice cores, tree rings and speleothems;
- The food web and migratory ecology of ecosystems in Alaska involving gray wolves, moose, salmon, caribou, polar bears, white-fronted geese, and seabirds; and
- Climate-plant-animal interactions in Arctic and temperate landscapes using experimental and observational studies.
- Lupascu, M., Welker, J. M., Seibt, U., Xu, X., Lindsey, D. S., Czimczik, C. I. (2013). The magnitude, seasonality and sources of CO2 emissions in a High Arctic polar semi-desert in NW Greenland are controlled by precipitation in puts and soil water conditions. Nature Climate Change (in press).
- Pattison, R., and Welker, J. M. (2013) Differential ecophysiological response of deciduous shrubs and a graminoid to long-term snow reductions and additions in moist acidic tundra, Northern Alaska. Oecologia (in press).
- Causey, D., Bargmann, N. A., Burnham, K. K., Burnham, J. L., Padula, V. M., Johnson, J. A., and Welker, J. M. (2013) Biogeochemical indicators in High- and Low-Arctic marine and terrestrial avian community changes: Comparative isotopic (?13C, ?15N) studies in Alaska and Greenland. Marine Biology (in press).
- Healey, N. Oberbauer, S., Ahrends, H. , Dierick, D., Welker, J. M. et al. (2013) A Mobile Instrumented Sensor Platform for Long-term Terrestrial Ecosystem Observation: A Case Study in the Arctic. J of Environmental Informatics (in press).
- Liu, Z., Bowen, G., Yoshimura, K., and Welker, J. M. (2013) Pacific North American teleconnection controls on precipitation isotopes (?18O) across the contiguous USA and adjacent regions. J. Climate doi:10.1175/JCLI-D-13-00334.1.
- Oberbauer, S. F., Elmendorf,, S. C., Troxler, T., Hollister, R. D., Welker, J. M., et al. (2013) Phenological responses of tundra plants to background climate variation tested using the International Tundra Experiment (ITEX) Proceedings of the Royal Academy 8 025023.
- Zeno, F., Siegel, D., Soumitri, S., Dasgupta, D, Glaser, P., Welker, J. M. (2013) Stable isotopes of peat pore water show seasonal recharge vertically penetrates both circumboreal bogs and fens. Hydrological Processes 10.1002/hyp.9983.
- Cable, J., Olge, K., Bolton, D., Bentley, L., Romonvsky, V., Iwata, H., Harazona, Y., and Welker, J. M. (2013) Permafrost thaw effects boreal deciduous plant through increased soil water, increased thaw and warmer temperatures. Ecohydrology DOI: 10.1002/eco.1423.
- Leffler, J. and Welker, J. M. (2013) Long-term increases in snow elevate leaf N and photosynthesis in Salix arctica: response to a snow fence experiment in NW Greenland. Environmental Research Letters 8, 025023
- Schaeffer, S. M., Sharp, E., Schimel, J. and Welker, J. M. (2013) Soil N processes in the High Arctic: Responses to a long-term multi-level warming and added summer water experiment. Global Change Biology DOI: 10.1111/gcb.12318.
- Sharp, E., Sullivan, P., Steltzer, H., Csank, A., and Welker, J. M. (2013) Complex carbon cycling responses to multi-level warming and supplemental summer rain in a High Arctic ecosystem. Global Change Biology DOI: 10.1111/gcb.12149.
(42 awards, exceeding $18,000,000)
(16 awards ~$9,000,000 since 2004, ~$6,000,000 to UAA)
1. Beard, K., Welker, J. M. and Leffler, J. (2013) Collaborative Research: Tropic mismatch between geese and wet sedge tundra. National Science Foundation, Office of Polar Programs, $1,277,065.
2. Welker, J. M. and Spalinger, D. (2012) Comparative ecology of caribou heards across Alaska: Collaborations between USFWS Land Conservation Consortiums. USGS Alaska Climate Science Center, $59,988.
3. Welker, J M., Cable, J., and Cherry, J. (2012) EAGER-Collaborative Research: Quantifying changes in the Arctic hydrological cycle at the landscape scale using advances in water vapor isotope (d18O and dD) techniques and aircraft. National Science Foundation, Office of Polar Programs, $288,000.
3. Post, E., Sullivan, P. F., Welker, J. M., and Eissenstat, D. M. (2011) Collaborative Research: Linking belowground phenology and ecosystem function in a warming Arctic. National Science Foundation, Office of Polar Programs. $1,300,000.
4. Gonzalez-Meler, M., Sturchio, N., Welker, J. M., and Filley, T.R. (2011) Collaborative Research: Permafrost thawing and vegetation change and effects on cryoturbation rates, CO2 and CH4 processes. Department of Energy, Terrestrial C cycle Research Program. $1,010,000.
5. Spalinger, D. E., Welker, J. M., Sullivan, P. F., and Collins, W. (2011) The Tundra in Transition: Unraveling the Dynamics of Western Alaska Caribou – Tundra Ecosystems. USFWS LCC program. $200,000.
6. Campbell, R., Welker, J. M., Crusius, J., Gasso, S., Schroth, A., and Thomas, A. (2010) Collaborative Research: Melting ice, habitat change and nutrient flux: Hydrological, biogeochemical and biological linkages between the Copper River watershed and the coastal Gulf of Alaska. NASA. $1,388,000.
7. Welker, J. M. (2010). Grey wolf diet ecology in Lake Clark National Park. National Park Service, Anchorage, Alaska. $102,766.
8. Welker, J. M., Buck, C. L., van Tets, I. G., Burns, J. M., and Cable, J. (2009) MRI Acquisition: Detecting and monitoring changes in the arctic using stable isotope techniques: A facility that contributes to IPY, NEON and beyond. NSF Major Research Instrumentation. $588,000.
9. Oberbauer, S., Welker, J. M., Sullivan, P. F., Tweedie, C., and Hollister, R. (2008)Collaborative Research: Sustaining and amplifying the ITEX AON through automation and increased interdisciplinarity of observations. NSF Office of Polar Programs, Arctic Observing Network. $1,233,000.
10. Czimczik, C. I., Welker, J. M., Sullivan, P. F., and Schimel, J. (2008) Collaborative Research: Processes governing the ages (14C) and magnitudes of ecosystem respiration in the High Arctic. NSF Office of Polar Programs. $1,250,000.
11. Cable, J., and Welker, J. M. (mentor). (2009) The consequences of permafrost degradation on plant-water use strategies. NSF Office of Polar Programs, Postdoctoral Fellowship. $208,000.
12. Hagedorn, B., Perry, M., Spalinger, D. E., and Welker, J. M. (2008) Enhancing Research and Education at the University of Alaska Anchorage with a state-of-the-art Liquid Chromatograph-Ion Trap Mass Spectrometer. NSF Major Research Instrumentation. $411,000.
13. Welker, J. M., Sveinbjörnsson, B., Sullivan, P. F. (2006) Mechanisms and feedback consequences of shrub expansion following long-term increases in winter snow depth in northern Alaska: a legacy for IPY. National Science Foundation, Office of Polar Programs. $622,000.
14. Welker, J. M., Sveinbjörnsson, B., Sullivan, P. F., and Boggs, K. (2006) IPY: Collaborative Research: Study of arctic ecosystem changes in the IPY using the International Tundra Experiment. NSF Office of Polar Programs. $257,000.
15. Welker, J. M., Sveinbjörnsson, B., Peterson, K., Olsson, P., Boggs, K, and Carlson, M. (2005) The UAA Boreal Forest Environmental Observatory (BFEO): A campus-based education and research platform that engages undergraduates and strengthens national funding competitiveness. UAA Enhancement Fund. $130,000.
16. Welker, J. M., Wipfli, M., and Rinella, D. (2005) UAA & UAF Collaborative Research: Comparative marine-terrestrial nitrogen linkages in streams of the Kenai Peninsula. UAA’s Chancellor’s Fund. $24,500.
17. Welker, J. M., Hallet, B., Sletten. R., Schimel, J., and Fahnestock, J. T. (2002) Collaborative Research: Coupling of carbon and water cycles in a cold, dry ecosystem: Integrative physical, chemical and biological processes and their controls on CO2 exchange. National Science Foundation, Biocomplexity in the Environment. $1,700,000.
18. Welker, J. M., and Fahnestock, J. T. (2001) Mixedgrass Prairie Responses to Simultaneous Increases in Winter Snow Depth and Changes in Summer Rainfall: C, N and H2O dynamics. National Institute of Global Climate Change, Great Plains Region, Department of Energy. $360,000.
19. Welker, J. M., Vance, G., Stahl, P. D., and Fahnestock, J. T. (2001) Controls of C sequestration on Northern Rocky Mountain Rangelands. USDA-NRI. $180,000.
20. Welker, J. M. and White, J. (2000) Isotopic (d18O & dD) characteristics of precipitation across the U. S.: Temporal patterns and controlling processes. National Science Foundation, Earth System History Program. $465,000.
21. Lockwood, J., Welker, J. M., and Kazmer, D. (2000) The Pied Piper IPM Strategy: Attracting rangeland grasshoppers with plant oils. USDA CSREES. $200,000.
22. Welker, J. M., Fahnestock, J. T., and Bilbrough, C. J. (1999) Species responses to changes in climate across arctic gradients using the North American ITEX network (NATEX): influences on community and ecosystem processes. NSF Office of Polar Programs. $475,000.
22. Molau, U., Henry, G., and Welker, J. M. (1998) Climatic impacts on annual growth and physiology in Cassiope tetragona. Swedish Royal Academy of Science, Polar Directorate, Tundra Northwest Expedition 1999. $150,000.
24. Welker, J. M., Poulson, S. Smith, W. K., Drever, T., Jackson, S. (1998) A stable isotope facility to study terrestrial processes and their interactions with climate and the environment. National Science Foundation, Major Research Instrumentation. $335,000.