Open AccessSeedability of Winter Orographic Clouds
Author(s) -
Geoffrey E. Hill
Publication year - 1986
Publication title -
meteorological monographs
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.32
H-Index - 3
eISSN - 1943-3646
pISSN - 0065-9401
DOI - 10.1175/0065-9401-21.43.127
Subject(s) - orographic lift , seeding , cloud seeding , precipitation , environmental science , supercooling , liquid water content , atmospheric sciences , meteorology , winter storm , wind speed , storm , climatology , cloud computing , geology , geography , physics , thermodynamics , computer science , operating system
This article is a review of work on the subject of seedability of winter orographic clouds for increasing precipitation. Various aspects of seedability are examined in the review, including definitions, distribution of supercooled liquid water, related meteorological factors, relationship of supercooled liquid water to storm stage, factors governing seedability, and the use of seeding criteria. Of particular interest is the conclusion that seedability is greatest when supercooled liquid water concentrations are large and at the same time precipitation rates are small. Such a combination of conditions is favored if the cloud-top temperature is warmer than a limiting value and as the cross-barrier wind speed at mountaintop levels increases. It is also suggested that cloud seeding is best initiated in accordance with direct measurements of supercooled liquid water, precipitation, and cross-barrier wind speed. However, in forecasting these conditions or in continuation of seeding previously initiated, the cloud-top temperature and cross-barrier wind speed are the most useful quantities.