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-surface temperatures observed in this case (from −3° to −1°C). We speculate that even weak transfers of moisture between the lake and atmosphere over high concentration ice may decrease the local responses in latent heat fluxes over small breaks in ice cover, resulting in more linear relationships between fluxes and pack ice concentration. d. Implications for late-winter lake-effect snow prediction The nonlinear relationship between sensible heat fluxes and surface ice concentrations appears to be the result of
-surface temperatures observed in this case (from −3° to −1°C). We speculate that even weak transfers of moisture between the lake and atmosphere over high concentration ice may decrease the local responses in latent heat fluxes over small breaks in ice cover, resulting in more linear relationships between fluxes and pack ice concentration. d. Implications for late-winter lake-effect snow prediction The nonlinear relationship between sensible heat fluxes and surface ice concentrations appears to be the result of
1. Introduction Since the early 1990s, Météo-France has used an automatic system based on three numerical models to simulate meteorological parameters, snow cover stratigraphy, and avalanche risk at various altitudes, aspects, and slopes for a number of mountainous regions (massifs) in France ( Durand et al. 1999 ). This SAFRAN–Crocus–MEPRA 1 (SCM) model chain, usually applied to operational avalanche forecasting, is used here for retrospective snow and weather climate analyses. A 10-yr snow
1. Introduction Since the early 1990s, Météo-France has used an automatic system based on three numerical models to simulate meteorological parameters, snow cover stratigraphy, and avalanche risk at various altitudes, aspects, and slopes for a number of mountainous regions (massifs) in France ( Durand et al. 1999 ). This SAFRAN–Crocus–MEPRA 1 (SCM) model chain, usually applied to operational avalanche forecasting, is used here for retrospective snow and weather climate analyses. A 10-yr snow
924 JOURNAL OF APPLIED METEOROLOGY VOLUldE6The Detection of Zinc Sulfide in Melted Snow S~mples~Bollay Assodate~, Inc., Boulder, Colo.(Manuscript received 9 May 1967) A modern Becquerel phosphososcope has been constructed for detecting zinc sulfide tracer in meltedsnow samples. The device utilizes the components of the real-time sensor described by Nickola e~ a/., adaptedto a rotating
924 JOURNAL OF APPLIED METEOROLOGY VOLUldE6The Detection of Zinc Sulfide in Melted Snow S~mples~Bollay Assodate~, Inc., Boulder, Colo.(Manuscript received 9 May 1967) A modern Becquerel phosphososcope has been constructed for detecting zinc sulfide tracer in meltedsnow samples. The device utilizes the components of the real-time sensor described by Nickola e~ a/., adaptedto a rotating
where frozen soil and persistent snow cover are common winterfeatures. Three distinct albedo periods were found, the occurrence of which can be explained by comparisonwith associated daily records of air temperature and snow depth. These periods are: I) Introduction to Winter,9-22 November, a transitional period in which snowfalls begin to occur but with insufficient frequency orduration to greatly alter the mean albedo from growing season values; II) the High Albedo Season, 23 November17 March
where frozen soil and persistent snow cover are common winterfeatures. Three distinct albedo periods were found, the occurrence of which can be explained by comparisonwith associated daily records of air temperature and snow depth. These periods are: I) Introduction to Winter,9-22 November, a transitional period in which snowfalls begin to occur but with insufficient frequency orduration to greatly alter the mean albedo from growing season values; II) the High Albedo Season, 23 November17 March
development and testing of the final global, regional lapse rate database that is being used in the CCPRS-4 cloud analyses. Two years of matched Aqua MODIS, CALIPSO, and CloudSat data are used to derive boundary layer monthly regional apparent lapse rates over ice-free water, snow-free land, and snow-covered surfaces for both daytime and nighttime. The parameters determined here are denoted as apparent lapse rates because they are based on satellite-derived cloud-top temperatures and surface skin
development and testing of the final global, regional lapse rate database that is being used in the CCPRS-4 cloud analyses. Two years of matched Aqua MODIS, CALIPSO, and CloudSat data are used to derive boundary layer monthly regional apparent lapse rates over ice-free water, snow-free land, and snow-covered surfaces for both daytime and nighttime. The parameters determined here are denoted as apparent lapse rates because they are based on satellite-derived cloud-top temperatures and surface skin
two equations of motion. The model includes variable snow and ice cover, meridional transport of heat and watervapor by mean and eddy atmospheric circulations, storage and transport of heat by the oceans, the effect ofaerosols on atmospheric turbidity, and the contribution of H20, COe, O~, and clouds to the infrared balance.Cloud cover, the surface relative humidity, and the surface albedo of snow- and ice-free areas are specified. Using present values for the input parameters, the model
two equations of motion. The model includes variable snow and ice cover, meridional transport of heat and watervapor by mean and eddy atmospheric circulations, storage and transport of heat by the oceans, the effect ofaerosols on atmospheric turbidity, and the contribution of H20, COe, O~, and clouds to the infrared balance.Cloud cover, the surface relative humidity, and the surface albedo of snow- and ice-free areas are specified. Using present values for the input parameters, the model
clear sky planetary aibedo is calculated by a radiative transfer model whichuses observed mean January and July earth properties on a global 5- x 5- grid. Our model calculationsaccount for the regional, zonal and seasonal variations in humidity, temperature, sea ice and snow cover.In addition, seasonal and zonal variations in ozone are included. We calculate the diurnal cycle of clear skyplanetary aibedo in the following spectral intervals: 0.2-0.5, 0.5-0.7 and 0.7-4 tzm. Model results revealthe
clear sky planetary aibedo is calculated by a radiative transfer model whichuses observed mean January and July earth properties on a global 5- x 5- grid. Our model calculationsaccount for the regional, zonal and seasonal variations in humidity, temperature, sea ice and snow cover.In addition, seasonal and zonal variations in ozone are included. We calculate the diurnal cycle of clear skyplanetary aibedo in the following spectral intervals: 0.2-0.5, 0.5-0.7 and 0.7-4 tzm. Model results revealthe
NOAA.5 Scanning Radiometerobservations is presented. Methods for isolating dear-sky observations from satellite data are evaluated and themagnitude of atmospheric effects (Rayleigh scattering and ozone absorption) are presented. A preliminaryanalysis of digital vegetation and soils data hoses, which were an alyzed in conjunction with the satellite observations,is discussed. Regional and global reflectance homogeneity of land-cover types, and snow brightening for types,are presented. Results
NOAA.5 Scanning Radiometerobservations is presented. Methods for isolating dear-sky observations from satellite data are evaluated and themagnitude of atmospheric effects (Rayleigh scattering and ozone absorption) are presented. A preliminaryanalysis of digital vegetation and soils data hoses, which were an alyzed in conjunction with the satellite observations,is discussed. Regional and global reflectance homogeneity of land-cover types, and snow brightening for types,are presented. Results
islands also exist. Hogan and Ferrick (1990) compared the temperatures observed along paved streets enclosed by low buildings in Hanover, New Hampshire, with several temperatures observed 1–2 km away in snow-covered terrain along open fields and recreation areas at the same elevation. A consistent difference of 1°–2°C was readily apparent, indicating that Lowry’s method is capable of isolating differences of this magnitude. The instrumentation used in obtaining these temperatures was a vehicle
islands also exist. Hogan and Ferrick (1990) compared the temperatures observed along paved streets enclosed by low buildings in Hanover, New Hampshire, with several temperatures observed 1–2 km away in snow-covered terrain along open fields and recreation areas at the same elevation. A consistent difference of 1°–2°C was readily apparent, indicating that Lowry’s method is capable of isolating differences of this magnitude. The instrumentation used in obtaining these temperatures was a vehicle
from the seeding track ( Fig. 20 ). Degree of riming determines how fast snow falls out. Snow fell out within 15–40 min on days (20 and 31 January) with greater LWC along and downwind of the seeding track, and widespread occurrence of supercooled drizzle. In summary, the greatest amount of LESnow, largest area covered by snowfall, and highest peak snowfall produced through seeding occurred on the day (31 January) with the largest and most widespread occurrence of supercooled drizzle, highest wind
from the seeding track ( Fig. 20 ). Degree of riming determines how fast snow falls out. Snow fell out within 15–40 min on days (20 and 31 January) with greater LWC along and downwind of the seeding track, and widespread occurrence of supercooled drizzle. In summary, the greatest amount of LESnow, largest area covered by snowfall, and highest peak snowfall produced through seeding occurred on the day (31 January) with the largest and most widespread occurrence of supercooled drizzle, highest wind
