Analysis of lake ice dynamics and morphology on Lake El'gygytgyn, NE Siberia, using synthetic aperture radar (SAR) and Landsat

Abstract

[1] A time series of more than 450 combined ERS-2, Radarsat-1, and Landsat-7 scenes acquired between 1998 and 2001 was analyzed to develop a fairly complete picture of lake ice dynamics on Lake El'gygytgyn, NE Siberia (67.5°N, 172°E). This 14-km 3 lake partially fills a meteorite impact crater formed 3.6 million years ago and is home to a paleoenvironmental coring project. The duration of lake ice cover and the onset of lake ice breakup are important both to interpretations of the archived sediment core record and to future drilling projects that will use the ice as a stable platform. Ice formation, snowmelt, and ice breakup likely occur in late October, mid-May, and early July, respectively. These data were used to validate a one-dimensional energy-balance lake ice model, which can now be used to hindcast paleoclimate based on core proxy information. Synthetic aperture radar (SAR) backscatter from the lake ice also revealed unusual spatial variations in bubble content, which were found to indicate the level of biological productivity in the sediments directly beneath the ice, with the highest productivity located in the shallowest (0-10 m) as well as the deepest (170-175 m) regions of the lake. Seismic data indicates that the backscatter anomaly above the deepest water is collocated with the central peak of the impact crater, 500 m below the surface. Several hypotheses are presented to explain this anomaly. Regardless of cause, the fact that large spatial variations in biological productivity exist in the lake has important implications for selecting the locations of future sediment cores.INDEX TERMS: 1640 Global Change: Remote sensing; 1845 Hydrology: Limnology; 1630 Global Change: Impact phenomena; 1863 Hydrology: Snow and ice (1827); 1878 Hydrology: Water/energy interactions; 1615 Global Change: Biogeochemical processes (4805); KEYWORDS: lake ice, energy balance, lake modeling, Chukotka, Russia, climate Citation: Nolan, M., G. Liston, P. Prokein, J. Brigham-Grette, V. L. Sharpton, and R. Huntzinger, Analysis of lake ice dynamics and morphology on Lake El'gygytgyn, NE Siberia, using synthetic aperture radar (SAR) and Landsat,

Applying SAR-IRSL methodology for dating fine-grained sediments from Lake El’gygytgyn, north-eastern Siberia

“…The open water season usually starts during the mid of July. A complete lake ice cover does not become formed again until Late October (Nolan et al, 2003).…”

Quantitative and qualitative constraints on hind-casting the formation of multiyear lake-ice covers at Lake El'gygytgyn

“…The 175 m deep, 12 km wide lake lies inside a 3.6 million year old meteorite impact crater that is 18 km wide and has presumably been filling with sediments since the time of the impact. The impact, the crater, the sediment core, and the physical environment are all well-described in a series of prior papers (Belya and Chershnev, 1993;Glushkova, 1993;Layer, 2000;Nowaczyk et al, 2002;Nolan et al, 2003;Cherapanova et al, 2007;Glushkova and Smirnov, 2007;Melles et al, 2007;Minyuk et al, 2007;Nolan and Brigham-Grette, 2007;Brigham-Grette, 2009;Swann et al, 2010) and those found in this special issue (Melles et al, 2012;Minyuk et al, 2013).…”

“…Our prior remote sensing from 1997-2001 indicates that snowmelt on the lake surface begins in mid-May, a moat forms at the edge of the lake ice in the last week of June, and complete ice melt occurs in mid-July. Once the moat opens up in June, the ice pack is subjected to substantially higher mechanical erosion due to wind shove, and our remote sensing data show (Nolan et al, 2003) that soon after moat formation, the ice pack forms major leads across the lake at deltas or outcrops that jut into the lake (e.g., at Stream 12 on the west side, Nolan and Brigham-Grette, 2007). During this time, about half the melt energy is supplied by solar absorption in the ice pack, and crystal grain boundaries weaken, forming candle ice which lacks the cohesion of the winter ice pack (Locke, 1990).…”

“…Ice growth on arctic lakes and rivers can be modeled reasonably successfully using freezing degree days and local tuning factors (USACE, 2004;Arp et al, 2010), in a much simpler way than our prior methods (Nolan et al, 2003). The model we use here (Eq.…”

“…Consequently, understanding the sensitivity of lake ice to climatic conditions is fundamental to the interpretation of sedimentary evidence of lake-water anoxia in terms of past climate variability. Nolan et al (2003), analyzed modern lake-ice cover in detail using four years of synthetic aperture radar (SAR) and Landsat remote sensing data in combination with a physically-based numerical model of lake-ice growth and decay. Modeled ice growth and decay closely matched the timing observed in the remote sensing data.…”