580 California St., Suite 400
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Key research themes
1. How can glacier inventories be improved and standardized using remote sensing and historical data for accurate glacier change assessment?
This theme focuses on the development, refinement, and validation of glacier inventories using a combination of satellite imagery, aerial photographs, historical maps, and manual delineation methods. Accurate glacier inventories are foundational for quantifying glacier extent, area, volume, and mass changes, which are essential for understanding glacier response to climate change. The integration of high-resolution data and methodological innovations addresses limitations in existing inventories, particularly in regions with complex terrain, small glaciers, or long historical timelines.
Key finding: Developed the GAMDAM glacier inventory (GGI) for high-mountain Asia using manual delineation from 356 Landsat ETM+ scenes (1999-2003), incorporating peer review to ensure quality. GGI delineates 87,084 glaciers covering... Read more
Key finding: Reconstructed glacier extents circa 1899 for Nordland using historical gradteigskart maps, validating outlines against geomorphological evidence and aerial photos. Established an overall area uncertainty of ±17%. This... Read more
Key finding: Produced the SGI2010 glacier inventory for the Swiss Alps via manual delineation from very high-resolution (25 cm) aerial orthophotographs from 2008-2011, improving precision especially for very small glaciers (<0.5 km²).... Read more
Key finding: Demonstrated the usability of declassified Hexagon KH-9 panoramic stereo imagery (1971-1984) to generate high-quality DEMs with <4 m elevation accuracy. KH-9PC data exhibit improved spatial coverage and reduced noise compared... Read more
Key finding: Compiled and analyzed comprehensive global glacier datasets from the World Glacier Monitoring Service (WGMS), confirming centennial-scale glacier retreat worldwide with no observed return to Little Ice Age maximums. The study... Read more
2. What are the observed patterns and magnitudes of glacier mass balance and volume changes in key mountain regions over recent decades?
This theme addresses the quantification of glacier mass balance changes using in situ measurements, geodetic surveys, and satellite remote sensing across diverse mountain ranges such as the Arctic, Himalaya, Central Andes, and North America. These studies provide vital empirical data documenting the rate and spatial variability of glacier mass loss, linking it to climate drivers, and evaluating impacts on water resources and sea-level contribution.
Key finding: Reviewing multiple glacier inventories and field data for Iceland's glaciers, the study indicates ongoing accelerated volume losses (e.g., ~10% reduction of Vatnajökull's volume since late 19th century, accelerated losses in... Read more
Key finding: Mapped debris-free glacier extent in Dhauliganga catchment for 2001 and 2020, documenting ~34% area loss (82 glaciers lost) with accelerated retreat on south-facing aspects. Geodetic assessment showed significant surface... Read more
Key finding: Presented an updated in situ mass-balance record (2011–2021) with an average of -0.39 ± 0.32 m w.e. per year and reconstructed long-term mass balance (1974–2021) using an energy-mass balance model. Modelled mass balance of... Read more
Key finding: Using the recent Argentinean National Glacier Inventory combined with satellite stereophotogrammetry derived glacier elevation changes, the study found a region-wide mass balance of -0.18 ± 0.19 m w.e. yr⁻¹ for 2000-2018.... Read more
3. How do glacier meltwater contributions affect regional hydrology and resource security under changing climatic conditions?
This theme investigates the critical role of glaciers as freshwater sources, their contributions to streamflow and hydropower generation, and implications for water, energy, and food security in mountain regions. It explores meltwater variability in response to climate change, the concept of peak water, and challenges in managing water resources amid glacier retreat, with a focus on socio-environmental feedbacks and downstream impacts.
Key finding: Quantified that 184 glaciers on the Olympic Peninsula declined by 34% in area since 1980, with accelerated volume loss causing significant runoff (9–15% of May–September streamflow, up to 30% in late summer). Findings... Read more
Key finding: Identified four primary factors leading to catastrophic large-scale glacier detachments at Flat Creek glacier: anomalously high meltwater input, weak glacier bed geology, inefficient subglacial drainage due to cold ice... Read more
Key finding: Documented that glaciers, though small and thin, contribute substantially during summer droughts to streamflow, buffering ecosystems and water supply. Mass loss and changes in precipitation phase (snow to rain) due to warming... Read more