국내 최대 기계 및 로봇 연구정보

기술보고서

기술보고서 게시판 내용
타이틀	Surface-Based Observations of Contrail Occurrence Frequency Over the U.S., April 1993--April 1994
저자	Patrick Minnis, J. Kirk Ayers and Steven P. Weaver
Keyword	Contrails; Cirrus clouds; Surface observation; Subsonic assessment; Aircraft effects; Climate change
URL	http://techreports.larc.nasa.gov/ltrs/PDF/1997/NASA-97-rp1404.pdf
보고서번호	NASA RP-1404
발행년도	1997
출처	NASA Langley Research Center
ABSTRACT	Surface observers stationed at 19 U.S. Air Force Bases and Army Air Stations recorded the daytime occurence of contrails and cloud fraction on an hourly basis for the period April 1993 through April 1994. Each observation uses one of four main categories to report contrails as unobserved, non-persistent, and indeterminate. Additional classification includes the co-occurence of cirrus with each report. The data cover much of the continental U.S. including locations near major commercial air routes. The mean annual frequency of occurrence in unobstructed viewing conditions is 13 percent for these sites. Contrail occurrence varied substantially with location and season. Most contrails occurred during the winter months and least during the summer with a pronounced minimum during July. Although nocturnal observations are not available, it appears that the contrails have a dirunal variation that peaks during mid morning over most areas. Contrails were most often observed in areas near major commerical air corridors and least often over areas far removed from the heaviest air traffic. A significant correlation exists between mean contrail frequency and aircraft fuel usage above 7 km suggesting predictive potential for assessing future contrail effects on climate.