Author: Richard K. Jeck
Publisher:
ISBN:
Category : Airplanes
Languages : en
Pages : 100
Book Description
About 7600 nautical miles (nm) (14,000 km) of select ice particle measurements over the United States have been compiled into a single, computerized database for use in characterizing ice crystal and snowflake (generally termed ice particle) size distributions and mass concentrations at flight altitudes. Data are from 50 research flights by six agencies in eight flight research projects using Particle Measuring Systems' one-dimensional (1-D) and two-dimensional (2-D) particle sizing probes. Primary recorded variables are average particle size distributions in the range 0.1 to 10 mm from each of 1625 microphysically uniform cloud intervals or other convenient distances in wintertime clouds, snowstorms, cirrus, and other high-altitude clouds. The findings are that, generally, the largest particles and the greatest concentrations of total ice particle mass (TIPM) are confined to altitudes below 20,000 ft (6 km). There, particles of 10 mm in maximum dimension and TIPM's up to about 3 g/m(exp 3) may be found. Above 20,000 ft, particles are smaller than 2 mm and TIPM's are less than 0.2 g/m(exp 3) in the cirrus and the upper reaches of deep winter storm clouds that are found at these levels. Exceptions are thunderstorm anvil clouds where 10 mm particles and TIPM's of at least 1 g/m(exp 3) can be found up to at least 30,000 ft (9 km). Anvil clouds and stratiform clouds associated with warm season mesoscale convective systems have provided some of the largest TIPM's, the greatest particle concentrations, and the largest particle sizes at high and mid altitudes, respectively. In contrast to supercooled cloud droplets where the largest liquid water (mass) concentrations are confined to short distances of 3 nm or less in convective clouds, the largest average TIPM's in glaciated clouds have been found in layer clouds over distances up to 30 nm.
Snow and Ice Particle Sizes and Mass Concentrations at Altitudes Up to 9 Km (30,000 Feet)
Author: Richard K. Jeck
Publisher:
ISBN:
Category : Airplanes
Languages : en
Pages : 100
Book Description
About 7600 nautical miles (nm) (14,000 km) of select ice particle measurements over the United States have been compiled into a single, computerized database for use in characterizing ice crystal and snowflake (generally termed ice particle) size distributions and mass concentrations at flight altitudes. Data are from 50 research flights by six agencies in eight flight research projects using Particle Measuring Systems' one-dimensional (1-D) and two-dimensional (2-D) particle sizing probes. Primary recorded variables are average particle size distributions in the range 0.1 to 10 mm from each of 1625 microphysically uniform cloud intervals or other convenient distances in wintertime clouds, snowstorms, cirrus, and other high-altitude clouds. The findings are that, generally, the largest particles and the greatest concentrations of total ice particle mass (TIPM) are confined to altitudes below 20,000 ft (6 km). There, particles of 10 mm in maximum dimension and TIPM's up to about 3 g/m(exp 3) may be found. Above 20,000 ft, particles are smaller than 2 mm and TIPM's are less than 0.2 g/m(exp 3) in the cirrus and the upper reaches of deep winter storm clouds that are found at these levels. Exceptions are thunderstorm anvil clouds where 10 mm particles and TIPM's of at least 1 g/m(exp 3) can be found up to at least 30,000 ft (9 km). Anvil clouds and stratiform clouds associated with warm season mesoscale convective systems have provided some of the largest TIPM's, the greatest particle concentrations, and the largest particle sizes at high and mid altitudes, respectively. In contrast to supercooled cloud droplets where the largest liquid water (mass) concentrations are confined to short distances of 3 nm or less in convective clouds, the largest average TIPM's in glaciated clouds have been found in layer clouds over distances up to 30 nm.
Publisher:
ISBN:
Category : Airplanes
Languages : en
Pages : 100
Book Description
About 7600 nautical miles (nm) (14,000 km) of select ice particle measurements over the United States have been compiled into a single, computerized database for use in characterizing ice crystal and snowflake (generally termed ice particle) size distributions and mass concentrations at flight altitudes. Data are from 50 research flights by six agencies in eight flight research projects using Particle Measuring Systems' one-dimensional (1-D) and two-dimensional (2-D) particle sizing probes. Primary recorded variables are average particle size distributions in the range 0.1 to 10 mm from each of 1625 microphysically uniform cloud intervals or other convenient distances in wintertime clouds, snowstorms, cirrus, and other high-altitude clouds. The findings are that, generally, the largest particles and the greatest concentrations of total ice particle mass (TIPM) are confined to altitudes below 20,000 ft (6 km). There, particles of 10 mm in maximum dimension and TIPM's up to about 3 g/m(exp 3) may be found. Above 20,000 ft, particles are smaller than 2 mm and TIPM's are less than 0.2 g/m(exp 3) in the cirrus and the upper reaches of deep winter storm clouds that are found at these levels. Exceptions are thunderstorm anvil clouds where 10 mm particles and TIPM's of at least 1 g/m(exp 3) can be found up to at least 30,000 ft (9 km). Anvil clouds and stratiform clouds associated with warm season mesoscale convective systems have provided some of the largest TIPM's, the greatest particle concentrations, and the largest particle sizes at high and mid altitudes, respectively. In contrast to supercooled cloud droplets where the largest liquid water (mass) concentrations are confined to short distances of 3 nm or less in convective clouds, the largest average TIPM's in glaciated clouds have been found in layer clouds over distances up to 30 nm.
Mixed-phase Icing Conditions
Author: James T. Riley
Publisher:
ISBN:
Category : Airplanes
Languages : en
Pages : 52
Book Description
Publisher:
ISBN:
Category : Airplanes
Languages : en
Pages : 52
Book Description
International Aerospace Abstracts
Journal of Aircraft
Dynamics of Snow and Ice Masses
Author: Samuel C. Colbeck
Publisher:
ISBN:
Category : Science
Languages : en
Pages : 488
Book Description
Dynamics of Snow and Ice Masses ...
Publisher:
ISBN:
Category : Science
Languages : en
Pages : 488
Book Description
Dynamics of Snow and Ice Masses ...
CRREL Bibliography
Perennial Ice and Snow Masses
Author: International Commission of Snow and Ice
Publisher:
ISBN:
Category : Glaciers
Languages : en
Pages : 164
Book Description
Publisher:
ISBN:
Category : Glaciers
Languages : en
Pages : 164
Book Description
Developing and Bounding Ice Particle Mass- and Area-dimension Expressions for Use in Atmospheric Models and Remote Sensing
Parameterizing Size Distribution in Ice Clouds
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
PARAMETERIZING SIZE DISTRIBUTIONS IN ICE CLOUDS David L. Mitchell and Daniel H. DeSlover ABSTRACT An outstanding problem that contributes considerable uncertainty to Global Climate Model (GCM) predictions of future climate is the characterization of ice particle sizes in cirrus clouds. Recent parameterizations of ice cloud effective diameter differ by a factor of three, which, for overcast conditions, often translate to changes in outgoing longwave radiation (OLR) of 55 W m-2 or more. Much of this uncertainty in cirrus particle sizes is related to the problem of ice particle shattering during in situ sampling of the ice particle size distribution (PSD). Ice particles often shatter into many smaller ice fragments upon collision with the rim of the probe inlet tube. These small ice artifacts are counted as real ice crystals, resulting in anomalously high concentrations of small ice crystals (D
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
PARAMETERIZING SIZE DISTRIBUTIONS IN ICE CLOUDS David L. Mitchell and Daniel H. DeSlover ABSTRACT An outstanding problem that contributes considerable uncertainty to Global Climate Model (GCM) predictions of future climate is the characterization of ice particle sizes in cirrus clouds. Recent parameterizations of ice cloud effective diameter differ by a factor of three, which, for overcast conditions, often translate to changes in outgoing longwave radiation (OLR) of 55 W m-2 or more. Much of this uncertainty in cirrus particle sizes is related to the problem of ice particle shattering during in situ sampling of the ice particle size distribution (PSD). Ice particles often shatter into many smaller ice fragments upon collision with the rim of the probe inlet tube. These small ice artifacts are counted as real ice crystals, resulting in anomalously high concentrations of small ice crystals (D
Field Measurements of Deposition Mode Ice Nucleating Particles at Puy de Dôme
Author: Megan M. Goodell
Publisher:
ISBN:
Category :
Languages : en
Pages : 24
Book Description
Ice nucleating particles are a critical aspect of the atmosphere to study due to their importance for cloud processes, weather, and climate. This thesis discusses deposition mode ice nucleating particle concentrations measured using the SPectrometer for Ice Nuclei at Puy de Dôme, France. These concentrations were most strongly dependent on source of the sampled air mass; meteorology and concentrations of gas phase species were poor predictors of INP abundance. Of particular interest is the distinct difference observed in activated fraction of particles between air masses from continental, marine, and new particle formation event sources, suggesting formation mechanism and particle chemistry as important factors in a particle's ability to nucleate ice. Analysis of new particle formation events also indicates that secondary organic aerosols derived from isoprene could be an important source of ice nucleating particles to consider.
Publisher:
ISBN:
Category :
Languages : en
Pages : 24
Book Description
Ice nucleating particles are a critical aspect of the atmosphere to study due to their importance for cloud processes, weather, and climate. This thesis discusses deposition mode ice nucleating particle concentrations measured using the SPectrometer for Ice Nuclei at Puy de Dôme, France. These concentrations were most strongly dependent on source of the sampled air mass; meteorology and concentrations of gas phase species were poor predictors of INP abundance. Of particular interest is the distinct difference observed in activated fraction of particles between air masses from continental, marine, and new particle formation event sources, suggesting formation mechanism and particle chemistry as important factors in a particle's ability to nucleate ice. Analysis of new particle formation events also indicates that secondary organic aerosols derived from isoprene could be an important source of ice nucleating particles to consider.