C. Duguay1, L.C. Brown2, K.-K. Kang1, H. Kheyrollah Pour1
1Interdisciplinary Centre on Climate Change & Department of Geography and Environmental Management,
University of Waterloo, Waterloo, ON, Canada
2Climate Research Division, Environment Canada, Downsview, ON, Canada
November 21, 2013
- Freeze-up in 2012 and break-up in 2013 both occurred earlier than the 2004-2012 average in most regions of the Arctic.
- Ice cover duration was shorter by ~1-4 weeks in regions adjacent to Hudson Bay, as well as in the western portion of the Canadian Arctic Archipelago, northern Alaska, Siberia and northern Scandinavia.
- Ice cover duration was longer by ~1-4 weeks for most parts of central to western Arctic Canada, southern Alaska, western Russia, southern Scandinavia and Baffin Island.
Lake ice is a sensitive indicator of climate variability and change. Lake ice phenology, which encompasses freeze-up (ice-on) and break-up (ice-off) dates, and ice cover duration, is largely influenced by air temperature changes and is therefore a robust indicator of regional climate conditions (Duguay et al. 2006, Kouraev et al. 2007). Long-term trends in ground-based observational records reveal increasingly later freeze-up and earlier break-up dates, closely corresponding to increasing air temperature trends, but with greater sensitivity at the more temperate latitudes (Brown and Duguay 2010, Prowse et al. 2011). Broad spatial patterns in these trends are also related to major atmospheric circulation patterns originating from the Pacific and Atlantic oceans such as the El Niño-La Niña/Southern Oscillation, the Pacific North American pattern, the Pacific Decadal Oscillation and the North Atlantic Oscillation/Arctic Oscillation (Bonsal et al. 2006, Prowse et al. 2011). Despite the robustness of lake ice as an indicator of climate change, a dramatic reduction in ground-based observational recordings has occurred globally since the 1980s (Lenormand et al. 2002, Duguay et al. 2006, IGOS 2007, Jeffries et al. 2012). Consequently, satellite remote sensing has assumed a greater role in observing lake ice phenology (Latifovic and Pouliot 2007, Brown and Duguay 2012, Kropáček et al. 2013, Surdu et al., 2013).
Ice phenology dates (freeze-up/ice-on and break-up/ice-off dates) and ice cover duration are derived from the NOAA Interactive Multisensor Snow and Ice Mapping System (IMS) 4 km resolution grid daily product for the 2012-2013 ice season over the Arctic, and are compared to average conditions for the length of the available satellite historical records. The IMS (Helfrich et al., 2007) incorporates a wide variety of satellite imagery, derived mapped products and surface observations. Ice-on and ice-off dates as well as ice duration were derived at the pixel level from this product. Freeze-up and break-up dates and ice-on and ice-off dates have the same meaning in this report.
Freeze-up (FU) in 2012-2013 occurred earlier than the 2004-2012 average by ~1-3 weeks for most regions of the Arctic (Fig. 59). Notable exceptions include lakes Ladoga and Onega (western Russia) and lakes of smaller size in southern Norway and adjacent areas of Sweden (~4-5 weeks earlier). Arctic-wide, a very few lakes experienced later FU than normal (~1-2 weeks later), and lakes in a small, localized region of lakes in southern Sweden experienced notably later FU than normal (~2-5 weeks). This is in contrast to the 2011-2012 ice season when FU occurred almost a full month later for most lakes located in the southern portion of northern Europe and part of the central portion of Arctic Canada (i.e., Great Slave Lake and Lake Athabasca regions) (Duguay et al. 2013).
Break-up (BU) dates in 2013 occurred ~1-3 weeks earlier than the 2004-2012 average over much of the Arctic, with the exception of Baffin Island and Ellesmere Island (Canada) (~1-4 weeks later) and the southern part of Scandinavia and western Russia (~1-5 weeks later) (Fig. 60). Lakes showing the largest BU anomalies with earlier dates (~3-4 weeks earlier) in 2013 are found in Siberia, consistent with spring-time positive air temperature anomalies and early snow cover loss (see the essays of Air Temperature and Snow). Break-up was also particularly early (by ~2-3 weeks ) in the western Hudson Bay and Victoria Island regions of Canada. Earlier BU anomalies of the same magnitude were reported throughout Siberia in 2012 (Duguay et al. 2013).
Ice Cover Duration
In general, the spatial pattern of ice cover duration (ICD, Fig. 61) anomalies followed closely that of BU anomalies. ICD for 2012-2013 was shorter by ~1-4 weeks in regions adjacent to Hudson Bay, as well as in the western section of the Canadian Arctic Archipelago (CAA), northern Alaska, Siberia and northern Scandinavia. ICD was longer by ~1-4 weeks for most parts of central to western Arctic Canada, southern Alaska, western Russia, southern Scandinavia, and on Baffin Island. A few exceptions include: (1) Canadian lakes Amadjuak and Nettilling (the largest lakes of Baffin Island) and Lake Hazen on Ellesmere Island, which experienced longer ICD by ~40-70 days, and (2) north European lakes Onega and Ladoga (western Russia), as well as smaller lakes to their south, and lakes in southern Norway. ICD was longer by ~50-80 days in 2012-2013 compared to the 2004-2012 average for these Russian and Norwegian lakes.
Bonsal, B. R., T. D. Prowse, C. R. Duguay, and M. P. Lacroix, 2006: Impacts of large-scale teleconnections on freshwater-ice duration over Canada. J. Hydrol., 330, 340-353.
Brown L. C., and C. R. Duguay, 2010: The response and role of ice cover in lake-climate interactions. Prog. Phys. Geogr., 34, 671-704.
Brown, L. C., and C. R. Duguay, 2012: Modelling lake ice phenology with an examination of satellite detected sub-grid cell variability, Adv. Meteorol., 2012, Article ID 529064, 19 pages, doi:10.1155/2012/529064.
Duguay, C., L. Brown, K.-K. Kang, and H. Kheyrollah Pour, 2013: [The Arctic] Lake ice [In "State of the Climate in 2012"]. Bull. Am. Meteorol. Soc., 94, S124-S126.
Duguay, C. R., T. D. Prowse, B. R. Bonsal, R. D. Brown, M. P. Lacroix, and P. Ménard, 2006: Recent trends in Canadian lake ice cover. Hydrol. Processes, 20, 781-801.
Helfrich, S. R., D. McNamara, B. H. Ramsay, T. Baldwin, and T. Kasheta, 2007: Enhancements to, and forthcoming developments in the Interactive Multisensor Snow and Ice Mapping System (IMS). Hydrol. Processes, 21, 1576-1586.
IGOS, 2007: Integrated Global Observing Strategy Cryosphere Theme Report - For the Monitoring of our Environment from Space and from Earth. World Meteorological Organization, WMO/TD-No. 1405, 100 pp.
Jeffries, M. O., K. Morris, and C. R. Duguay, 2012: Floating ice: lake ice and river ice. Satellite Image Atlas of Glaciers of the World - State of the Earth's Cryosphere at the Beginning of the 21st Century: Glaciers, Global Snow Cover, Floating Ice, and Permafrost and Periglacial Environments, R. S. Williams, Jr. and J. G. Ferrigno, Ed., U.S. Geological Survey Professional Paper 1386-A, A381-A424.
Kouraev, A. V., S. V. Semovski, M. N. Shimaraev, N. M. Mognard, B. Légresy, and F. Remy, 2007: Observations of Lake Baikal ice from satellite altimetry and radiometry. Remote Sens. Environ., 108, 240-253.
Kropáček, J., F. Maussion, F. Chen, S. Hoerz, and V. Hochschild, 2013: Analysis of ice phenology of lakes on the Tibetan Plateau from MODIS data. The Cryosphere, 7, 287-301.
Latifovic, R., and D. Pouliot, 2007: Analysis of climate change impacts on lake ice phenology in Canada using the historical satellite data record. Remote Sens. Environ., 16, 492-507.
Lenormand, F., C. R. Duguay, and R. Gauthier, 2002: Development of a historical ice database for the study of climate change in Canada. Hydrol. Processes, 16, 3707-3722.
Prowse, T., K. Alfredsen, S. Beltaos, B. Bonsal, C. Duguay, A. Korhola, J. McNamara, W. F. Vincent, V. Vuglinsky, and G. A. Weyhenmeyer, 2011: Past and future changes in lake and river ice. Ambio, 40 (S1), 53-62.
Surdu, C., C. R. Duguay, L. C. Brown, and D. Fernández Prieto, 2013: Response of ice cover on shallow lakes of the North Slope of Alaska to contemporary climate conditions (1950-2011): radar remote sensing and numerical modeling data analysis, The Cryosphere Discussion, 7, 3783-3821.