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1. Introduction The transport of snow by wind is prevalent over tundra, high to midlatitude grasslands, high-altitude steppes, alpine zones, and ice sheets ( Berg 1986 ; Petropavlovskaya and Kalyuzhnyi 1986 ; Groisman et al. 1997 ; Mann et al. 2000 ). Observations of the frequency of occurrence of blowing-snow events range between 16 to 35 days a year in northern Kazahkhstan ( Petropavlovskaya and Kalyuzhnyi 1986 ) to over 90 days a year along the Russian Arctic coastal plain and in the
1. Introduction The transport of snow by wind is prevalent over tundra, high to midlatitude grasslands, high-altitude steppes, alpine zones, and ice sheets ( Berg 1986 ; Petropavlovskaya and Kalyuzhnyi 1986 ; Groisman et al. 1997 ; Mann et al. 2000 ). Observations of the frequency of occurrence of blowing-snow events range between 16 to 35 days a year in northern Kazahkhstan ( Petropavlovskaya and Kalyuzhnyi 1986 ) to over 90 days a year along the Russian Arctic coastal plain and in the
annually on the Arctic tundra ( Phillips 1990 ). Its scarce vegetation and long seasonal snow covers make the Arctic tundra especially susceptible to blowing snow and blizzard events ( Déry and Yau 1999b ). Apart from its hazardous aspects such as reduced optical visibilities, blowing snow associated with blizzards and other high-wind events is of much interest because of its twofold contribution to the surface water and energy budgets through mass divergence or convergence in addition to concurrent in
annually on the Arctic tundra ( Phillips 1990 ). Its scarce vegetation and long seasonal snow covers make the Arctic tundra especially susceptible to blowing snow and blizzard events ( Déry and Yau 1999b ). Apart from its hazardous aspects such as reduced optical visibilities, blowing snow associated with blizzards and other high-wind events is of much interest because of its twofold contribution to the surface water and energy budgets through mass divergence or convergence in addition to concurrent in
“blizzard alley.” The frequency of blizzard conditions at most other stations north of the treeline is between about 0.5%–1.5% of hourly observations and is even lower in sheltered locations, particularly those in the rugged eastern and northern Arctic terrain. There, blizzard conditions may not occur at an observing site while they are simultaneously occurring in nearby open country. For example Dewar Lakes, located on high open tundra in the middle of Baffin Island, recorded a much higher frequency of
“blizzard alley.” The frequency of blizzard conditions at most other stations north of the treeline is between about 0.5%–1.5% of hourly observations and is even lower in sheltered locations, particularly those in the rugged eastern and northern Arctic terrain. There, blizzard conditions may not occur at an observing site while they are simultaneously occurring in nearby open country. For example Dewar Lakes, located on high open tundra in the middle of Baffin Island, recorded a much higher frequency of
, https://doi.org/10.1371/journal.pone.0155932 . 10.1371/journal.pone.0155932 Bhatt , U. S. , and Coauthors , 2010 : Circumpolar Arctic tundra vegetation change is linked to sea ice decline . Earth Interact. , 14 , 1 – 20 , https://doi.org/10.1175/2010EI315.1 . 10.1175/2010EI315.1 Bhatt , U. S. , and Coauthors , 2013 : Recent declines in warming and vegetation greening trends over pan-Arctic tundra . Remote Sens. , 5 , 4229 – 4254 , https://doi.org/10.3390/rs5094229 . 10.3390/rs5094229
, https://doi.org/10.1371/journal.pone.0155932 . 10.1371/journal.pone.0155932 Bhatt , U. S. , and Coauthors , 2010 : Circumpolar Arctic tundra vegetation change is linked to sea ice decline . Earth Interact. , 14 , 1 – 20 , https://doi.org/10.1175/2010EI315.1 . 10.1175/2010EI315.1 Bhatt , U. S. , and Coauthors , 2013 : Recent declines in warming and vegetation greening trends over pan-Arctic tundra . Remote Sens. , 5 , 4229 – 4254 , https://doi.org/10.3390/rs5094229 . 10.3390/rs5094229
nearby Arctic Ocean and typically overflew the surface Atmospheric Radiation Measurement (ARM) site in Barrow, Alaska, en route to and from the SHEBA ice station. The main objectives of the ER-2 included (i) comparing the spectral properties of sea ice, tundra, and cloud layers; (ii) collecting MAS data to verify the MODIS cloud mask algorithm for distinguishing clouds from snow and sea ice surfaces in polar regions; (iii) collecting data for retrieving cloud radiative and microphysical properties
nearby Arctic Ocean and typically overflew the surface Atmospheric Radiation Measurement (ARM) site in Barrow, Alaska, en route to and from the SHEBA ice station. The main objectives of the ER-2 included (i) comparing the spectral properties of sea ice, tundra, and cloud layers; (ii) collecting MAS data to verify the MODIS cloud mask algorithm for distinguishing clouds from snow and sea ice surfaces in polar regions; (iii) collecting data for retrieving cloud radiative and microphysical properties
disappeared, has albedo values averaging 0.18 over tundra and 0.08 over lakes. The autumn transitional period, starting from early September to mid-October, is characterized by large surface albedo due to occasional snowfalls and alternating periods of freezing and thawing. Other studies at Barrow have suggested somewhat a basis for dividing the year into seasons or periods. An intensive field investigation of the microclimates of the arctic tundra at Barrow, Alaska, was carried out during 1971 and 1972
disappeared, has albedo values averaging 0.18 over tundra and 0.08 over lakes. The autumn transitional period, starting from early September to mid-October, is characterized by large surface albedo due to occasional snowfalls and alternating periods of freezing and thawing. Other studies at Barrow have suggested somewhat a basis for dividing the year into seasons or periods. An intensive field investigation of the microclimates of the arctic tundra at Barrow, Alaska, was carried out during 1971 and 1972
υE strongly differs for high and low vegetation. On average, the relative error is less for high than for low vegetation. It is the highest for wooded tundra (up to 25.27% on average; Table 5 ). This means that distinguishing more types of tundra may yield improvement of latent heat flux prediction in the Arctic. Generally, σ L υE increases nonlinearly with vegetation fraction. This increase is usually (slightly) greater under warmer than cooler conditions ( Fig. 4 ). Superimposed is a
υE strongly differs for high and low vegetation. On average, the relative error is less for high than for low vegetation. It is the highest for wooded tundra (up to 25.27% on average; Table 5 ). This means that distinguishing more types of tundra may yield improvement of latent heat flux prediction in the Arctic. Generally, σ L υE increases nonlinearly with vegetation fraction. This increase is usually (slightly) greater under warmer than cooler conditions ( Fig. 4 ). Superimposed is a
prognostic atmospheric model component and the RUC LSM option as its land surface component. With the RAP domain extending into the Arctic region ( Fig. 1 ), the RUC LSM needed further development to improve an interactive coupling of the atmosphere with the underlying surface where it is ice covered. Fig . 1. Topography image (elevation in meters) of the North America RAP domain with embedded RUC domain also shown [assumed to be equal to the conterminous United States (CONUS) in this paper]. As a first
prognostic atmospheric model component and the RUC LSM option as its land surface component. With the RAP domain extending into the Arctic region ( Fig. 1 ), the RUC LSM needed further development to improve an interactive coupling of the atmosphere with the underlying surface where it is ice covered. Fig . 1. Topography image (elevation in meters) of the North America RAP domain with embedded RUC domain also shown [assumed to be equal to the conterminous United States (CONUS) in this paper]. As a first
the increase in surface winter temperature in Europe and Asia (north of 40°N) ( Hurrell 1996 ; Hurrell and van Loon 1997 ; Thompson et al. 2000 ; Hurrell et al. 2003 ). A mode of climate variability with extensive effects in the Northern Hemisphere, is the northern annular mode (NAM) ( Thompson and Wallace 2001 ), which also goes by the name of the North Atlantic Oscillation (NAO) ( Hurrell 1995 ) or the Arctic Oscillation (AO) ( Thompson and Wallace 1998 ). Thompson and Wallace (2001
the increase in surface winter temperature in Europe and Asia (north of 40°N) ( Hurrell 1996 ; Hurrell and van Loon 1997 ; Thompson et al. 2000 ; Hurrell et al. 2003 ). A mode of climate variability with extensive effects in the Northern Hemisphere, is the northern annular mode (NAM) ( Thompson and Wallace 2001 ), which also goes by the name of the North Atlantic Oscillation (NAO) ( Hurrell 1995 ) or the Arctic Oscillation (AO) ( Thompson and Wallace 1998 ). Thompson and Wallace (2001
Prof. Chapman was the official delegate of the American Meteorological Society to the XVIIth International Geological Congress held in Russia last summer; this report of his visit to some of the USSR polar meteorological stations should be of much interest to American meteorologists, because our continent has the same kind of meteorological-geographical relations to the Arctic Ocean: a large extent of low tundra land in the north reaching to the 80th parallel over which polar continental air builds up and finds a chute to slip its chilly freight directly into lower latitudes; we too have a chain of high-latitude meteorological stations to warn us of polar outbreaks. However, information from north of Siberia (Wrangell Is. region) seems to be almost as important to us as that from Alaska and northern Canada and Greenland; daily reports are now being received here from the more easterly section of the Siberian Arctic coast, thanks to the stations opened there by the Soviets and to their cooperation in transmitting them more quickly and directly than possible heretofore. The meteorological and aerological observations from the Russian polar stations are summarized and published in the “10-day bulletins of the General Admin, of the No. Sea Routes” (Moscow) and in the “Bulletins” and “Transactions of the Arctic Institute” (Leningrad). A discussion of the radiometeoro graph soundings made at some of these stations appeared in the October Bulletin Amer. Met. Soc., pp. 322 ff.—Editor.
Prof. Chapman was the official delegate of the American Meteorological Society to the XVIIth International Geological Congress held in Russia last summer; this report of his visit to some of the USSR polar meteorological stations should be of much interest to American meteorologists, because our continent has the same kind of meteorological-geographical relations to the Arctic Ocean: a large extent of low tundra land in the north reaching to the 80th parallel over which polar continental air builds up and finds a chute to slip its chilly freight directly into lower latitudes; we too have a chain of high-latitude meteorological stations to warn us of polar outbreaks. However, information from north of Siberia (Wrangell Is. region) seems to be almost as important to us as that from Alaska and northern Canada and Greenland; daily reports are now being received here from the more easterly section of the Siberian Arctic coast, thanks to the stations opened there by the Soviets and to their cooperation in transmitting them more quickly and directly than possible heretofore. The meteorological and aerological observations from the Russian polar stations are summarized and published in the “10-day bulletins of the General Admin, of the No. Sea Routes” (Moscow) and in the “Bulletins” and “Transactions of the Arctic Institute” (Leningrad). A discussion of the radiometeoro graph soundings made at some of these stations appeared in the October Bulletin Amer. Met. Soc., pp. 322 ff.—Editor.
