PhD, University of Colorado at Boulder, 1985
Remote sensing of snow, ice, and frozen ground; physical and mechanical properties of snow; snow cover and glacier mass/extent as indicators of climate change.
Recent Highlights and Upcoming Expeditions
- December 2011: Armstrong and colleague Mark Williams of the Institute of Arctic and Alpine Researh are partnering with the United States Agency for International Development, leading a study to assess snow and glacier contributions to water resources originating in the high mountains of Asia that straddle 10 countries.
- December 2009: Armstrong participated in a six-person task force to produce Melting Snow and Ice: A Call for Action (PDF file, 12.2 MB), a report on the status of Earth's glaciers and ice caps, which was presented at the United Nations Climate Change Conference in Copenhagen (COP15).
- May 2008: Armstrong became NSIDC Interim Director.
- October 2007: The Intergovernmental Panel on Climate Change (IPCC) was named to receive the 2007 Nobel Peace Prize, along with former Vice President Al Gore. Armstrong contributed to the most recent IPCC report, Climate Change 2007: The Physical Science Basis.
- October 2007: Briefed former Vice President Al Gore on snow and glaciers
- Developed and distributed a global snow extent and snow water equivalent data set for 1987 to 2005
- Enhancing methods to map global snow cover by combining optical data from MODIS and passive microwave data from AMSR-E
- Mapping glaciers at two spatial resolutions using data from ASTER (60 meter) and MODIS (500 meter)
- Investigating temporal and spatial snow cover distribution over the Tibetan Plateau and the synoptic patterns contributing to extreme winter snowfall events
- Studying microwave sensor calibration: Developing a systematic method to evaluate the spatial and temporal variability of brightness temperatures over selected land surface types (ice sheets and tropical forests) to locate stable calibration targets
- Managing the NSIDC State of the Cryosphere Web site
Member, American Geophysical Union
Member, International Glaciological Society
Member, International Association of Hydrological Sciences (IAHS)
International Commission on Snow and Ice (ICSI) representative, International Association of Hydrological Sciences (IAHS)
Chairman, ICSI Snow and Climate Working Group
Armstrong, R. L. 2010. The Glaciers of the Hindu Kush-Himalayan Region. Kathmandu, Nepal: International Centre for Integrated Mountain Development.
Elder, K., D. Cline, G. E. Liston, and R. Armstrong. 2009. NASA Cold Land Processes Experiment (CLPX 2002/03): Field Measurements of Snowpack Properties and Soil Moisture. Journal of Hydrometeorology 10(1): 320-329, doi:10.1175/2008JHM877.1.
Savoie, M. H., R. L. Armstrong, M. J. Brodzik, J. R. Wang. 2009. Atmospheric corrections for improved satellite passive microwave snow cover retrievals over the Tibet Plateau. Remote Sensing of the Environment 113(12): 2661-2669, doi:10.1016/j.rse.2009.08.006.
Armstrong, R. L., and E. Brun, eds. 2008. Snow and Climate: Physical Processes, Surface Energy Exchange and Modeling. Cambridge: Cambridge University Press.
Barry, R. G., R. Armstrong, T. Callaghan, J. Cherry, S. Gearheard, A. Nolin, D. Russell, and C. Zaeckler. 2007. Chapter 4: Snow. In Global outlook for ice and snow, ed. United Nations Environment Programme, 39-62. Hertfordshire, England: Earthprint.
Beedle, M. J., M. Dyurgerov, W. Tangborn, S. J. S. Khalsa, C. Helm, B. Raup, R. Armstrong, and R. G. Barry. 2007. Improving estimation of glacier volume change: a GLIMS case study of Bering Glacier System, Alaska. The Cryosphere Discussion 2(1): 33-51.
Raup, B., A. Racoviteanu, S. J. S. Khalsa, C. Helm, R. Armstrong, and Y. Arnaud. 2007. The GLIMS geospatial glacier database: A new tool for studying glacier change. Global and Planetary Change 56(1-2): 101-110, doi:10.1016/j.gloplacha.2006.07.018.
Yang, D., Y. Zhao, R. Armstrong, D. Robinson, and M. J. Brodzik. 2008. Streamflow response to seasonal snow cover mass changes over large Siberian watersheds. Journal of Geophysical Research 112, F02S22, doi:10.1029/2006JF000518.
Tedesco, M., E. J. Kim, D. Cline, T. Graf, T. Koike, R. Armstrong, M. J. Brodzik, and J. Hardy. 2006. Comparison of local scale measured and modeled brightness temperatures and snow parameters from the CLPX 2003 by means of a dense medium radiative transfer theory model. Hydrological Processes 20(4): 657-672, doi:10.1002/hyp.6129.
Chang, A. T. C., R. E. J. Kelly, E. G. Josberger, R. L. Armstrong, J. L. Foster, and N. M. Mognard. 2005. Analysis of ground-measured and passive-microwave-derived snow depth variations in midwinter across the northern Great Plains. Journal of Hydrometeorology 6(1): 20-33, doi:10.1175/JHM-405.1.
Zhang, T., R. G. Barry, and R. L. Armstrong. 2004. Application of satellite remote sensing techniques to frozen ground studies. Polar Geography 28(3):163-196.
Oelke, C., T. Zhang, M. C. Serreze and R. L. Armstrong, 2003. Regional-scale modeling of soil freeze/thaw over the Arctic drainage basin. Journal of Geophysical Research 108(D10): 4,314-4,331, doi:10.1029/2002JD002722.
Zhang, T., R. L. Armstrong, and J. Smith. 2003. Investigation of the near-surface soil freeze-thaw cycle in the contiguous United States: Algorithm development and validation. Journal of Geophysical Research 108(D22): 8860-8874, doi:10.1029/2003JD003530.
Armstrong, R. L., and M. J. Brodzik. 2002. Hemispheric-scale comparison and evaluation of passive microwave snow algorithms. Annals of Glaciology 34: 38-44, doi:10.3189/172756402781817428.
Frei, A., R. L. Armstrong, M. P. Clark, and M. Serreze. 2002. Catskill Mountains water resources: vulnerability, hydroclimatology and climate change sensitivity. Annals of the Association of American Geographers 92(2): 203-224.
Armstrong, R. L., and M. J. Brodzik. 2001. Recent Northern Hemisphere snow extent: a comparison of data derived from visible and microwave sensors. Geophysical Research Letters 28 (19): 3673-3676.
Tait, A. B., D. K. Hall, J. L. Foster, and R. L. Armstrong. 2000. Utilizing multiple data sets for snow-cover mapping. Remote Sensing of the Environment 72(1): 111-126.