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Winter conditions play an important role for the largest lake in Europe—Lake Ladoga. The ice cover lasts for 171 ± 3 days on average from the early November until the mid‐May. We investigated the ice regime of Lake Ladoga using a constructed ice database of aircraft surveys and satellite images. More than 1250 surveys of the lake's ice cover from 1943 to 2010 were collected and analysed to determine mean and extreme ice conditions for winters of different types of severity. The time series of ice cover percentage over the lake was plotted. On average, 18 observational ice charts were made every winter. Individual ice phenology records show considerable year‐to‐year variation. For this reason, records typically have been combined and analysed as groups (categories). Extremely cold winters were determined as winters with complete ice cover that lasts more than three months which is approximately 90% quartiles from all winters with complete ice cover. The lake surface was completely covered with ice for more than three months during 5 seasons. Extremely warm winters when the maximum ice cover was less than 70% of the lake area occurred during 5 seasons as well. A basic relationship between the winter severity as winter maximum of accumulated freezing degree‐days (AFDD) and the earlier derived Relative Ice Cover Index (RICI) was established. We have used teleconnection indices such as North Atlantic Oscillations (NAO) and Arctic Oscillation (AO) for the period from October to May for estimation of different types of Lake Ladoga's ice conditions. The AO index in winter months and local winter maximum of AFDD explained much of the interannual variation in ice cover. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
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Naumenko M. A. Guzivaty V. V. Dudakova D. S. Dudakov M. O. Anokhin V. M. 《Doklady Earth Sciences》2022,507(1):959-963
Doklady Earth Sciences - Based on the first created digital model of the Valaam archipelago (Lake Ladoga) with a spatial resolution of 25 × 25 m, a quantitative assessment of the spatial... 相似文献
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S. G. Karetnikov M. A. Naumenko V. V. Guzivatyi M. N. Shimaraev A. V. Kuraev 《Geography and Natural Resources》2016,37(2):135-143
We examine the dependence of the ice conditions for two major lakes of Asia and Europe: Baikal and Ladoga, on regional values of the arithmetic sums of mean daily winter air temperatures and global atmospheric processes expressed by atmospheric circulation indices. By ranking the winters according to the sums of mean daily winter air temperatures, it was possible to identify winters of the same type of severity for the regions of Baikal and Ladoga. The winters of the same type show an enhancement in correlations between ice characteristics with respect to the sums of winter air temperatures and atmospheric circulation indices as well as ice characteristics of the two lakes. It is shown that the interannual changers in characteristics of ice regime of Ladoga and Baikal are largely determined by the same atmospheric processes. The role of the circulation is most clearly manifested in variation of temperature regime indicators. Thus, the sums of air temperatures accumulated during a winter in the regions of these lakes show primarily the closest correlation with the Arctic and North Atlantic oscillation indices. 相似文献
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Yu V. Naumenko 《International Journal of Salt Lake Research》1999,8(2):171-176
The algal flora of Lake Bai-Khol, located in the endorheic Uvs-Nuur Basin, Russia, has been studied from collections made
in August 1997. 79 taxa belonging to diatoms, blue-green and green algae were present. 相似文献
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Ice and Snow Cover of Continental Water Bodies from Simultaneous Radar Altimetry and Radiometry Observations 总被引：1，自引：0，他引：1
A. V. Kouraev M. N. Shimaraev P. I. Buharizin M. A. Naumenko J.-F. Crétaux N. Mognard B. Legrésy F. Rémy 《Surveys in Geophysics》2008,29(4-5):271-295
We show how the studies of ice and snow cover of continental water bodies can benefit from the synergy of more than 15 years-long simultaneous active (radar altimeter) and passive (radiometer) observations from radar altimetric satellites (TOPEX/Poseidon, Jason-1, ENVISAT and Geosat Follow-On) and how this approach can be complemented by SSM/I passive microwave data to improve spatial and temporal coverage. Five largest Eurasian continental water bodies—Caspian and Aral seas, Baikal, Ladoga and Onega lakes are selected as examples. First we provide an overview of ice regime and history of ice studies for these seas and lakes. Then a summary of the existing state of the art of ice discrimination methodology from altimetric observations and SSM/I is given. The drawbacks and benefits of each type of sensor and particularities of radiometric properties for each of the chosen water bodies are discussed. Influence of sensor footprint size, ice roughness and snow cover on satellite measurements is also addressed. A step-by-step ice discrimination approach based on a combined use of the data from the four altimetric missions and SSM/I is presented, as well as validation of this approach using in situ and independent satellite data in the visible range. The potential for measurement of snow depth on ice from passive microwave observations using both altimeters and SSM/I is addressed and a qualitative comparison of in situ snow depth observations and satellite-derived estimates is made. 相似文献
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M. A. Naumenko V. V. Gyzivaty S. G. Karetnikov T. N. Petrova E. V. Protopopova A. M. Kryuchkov 《Doklady Earth Sciences》2012,444(1):601-605
The subsatellite experiment ??Thermal Front in Lake Ladoga, 2010?? and its results are described. The experiment was performed at the initial stages of thermal bar existence at the end of May 2010. We estimated the horizontal gradients of water temperature and the front motion rate by two successive surveys carried out with a discreteness of four days. Cumulative heat flows coming to the lake surface were different on different front sides. The hydrochemical and hydrobiological parameters of the front zone were not characterized by any significant horizontal differences. 相似文献
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Results of studying characteristic features of variability of the water surface temperature fields of Lake Ladoga during the
open water period are presented. Anomalies and extreme deviations of real spatial distributions from those typical of the
scales of synoptic variability are estimated. Typical surface temperature distribution of Lake Ladoga during an open water
period occupies not more than 20% of the lake area. The near-shore shallow water area is characterized as an area of most
anomalous water temperature distribution. The abnormality extent changes from month to month. July is the most anomalous month
of the open water period. 相似文献
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Naumenko M. A. Guzivaty V. V. Nesterov N. A. Sybetto D. A. 《Doklady Earth Sciences》2019,486(1):585-587
Doklady Earth Sciences - A digital bathymetric model with a 10 × 10 m spatial resolution was created on the basis of the depth sounding on the southwestern slope of Valaam Island with the use... 相似文献