globalchange  > 影响、适应和脆弱性
DOI: 10.1002/2013JD019700
论文题名:
Adjusting thresholds of satellite-based convective initiation interest fields based on the cloud environment
作者: Jewett C.P.; Mecikalski J.R.
刊名: Journal of Geophysical Research Atmospheres
ISSN: 21698996
出版年: 2013
卷: 118, 期:22
起始页码: 12649
结束页码: 12660
语种: 英语
英文关键词: convective initiation ; remote sensing ; threshold adjustment
Scopus关键词: Alarm systems ; Algorithms ; Clouds ; Errors ; Geostationary satellites ; Remote sensing ; Algorithm performance ; Cloud environments ; Convective initiation ; Environmental information ; Growth characteristic ; Number of false alarms ; Precipitation process ; Threshold adjustments ; Precipitation (meteorology) ; accuracy assessment ; algorithm ; atmospheric convection ; atmospheric modeling ; cloud cover ; cumulus ; geostationary satellite ; hydrometeorology ; threshold
英文摘要: The Time-Space Exchangeability (TSE) concept states that similar characteristics of a given property are closely related statistically for objects or features within close proximity. In this exercise, the objects considered are growing cumulus clouds, and the data sets to be considered in a statistical sense are geostationary satellite infrared (IR) fields that help describe cloud growth rates, cloud top heights, and whether cloud tops contain significant amounts of frozen hydrometeors. In this exercise, the TSE concept is applied to alter otherwise static thresholds of IR fields of interest used within a satellite-based convective initiation (CI) nowcasting algorithm. The convective environment in which the clouds develop dictate growth rate and precipitation processes, and cumuli growing within similar mesoscale environments should have similar growth characteristics. Using environmental information provided by regional statistics of the interest fields, the thresholds are examined for adjustment toward improving the accuracy of 0-1 h CI nowcasts. Growing cumulus clouds are observed within a CI algorithm through IR fields for many 1000 s of cumulus cloud objects, from which statistics are generated on mesoscales. Initial results show a reduction in the number of false alarms of ∼50%, yet at the cost of eliminating approximately ∼20% of the correct CI forecasts. For comparison, static thresholds (i.e., with the same threshold values applied across the entire satellite domain) within the CI algorithm often produce a relatively high probability of detection, with false alarms being a significant problem. In addition to increased algorithm performance, a benefit of using a method like TSE is that a variety of unknown variables that influence cumulus cloud growth can be accounted for without need for explicit near-cloud observations that can be difficult to obtain. Key Points Adjusting thresholds eliminates ∼50% of false alarms Adjusting thresholds also eliminates ∼20% of hits Including model variables could further reduce false alarms ©2013. American Geophysical Union. All Rights Reserved.
资助项目: NNX08AN81G
Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/63139
Appears in Collections:影响、适应和脆弱性
气候减缓与适应

Files in This Item:

There are no files associated with this item.


作者单位: Earth System Science Center, National Space Science and Technology Center, University of Alabama in Huntsville, 320 Sparkman Drive, Huntsville, AL 35805-1912, United States; Atmospheric Science Department, University of Alabama in Huntsville, Huntsville, AL, United States

Recommended Citation:
Jewett C.P.,Mecikalski J.R.. Adjusting thresholds of satellite-based convective initiation interest fields based on the cloud environment[J]. Journal of Geophysical Research Atmospheres,2013-01-01,118(22)
Service
Recommend this item
Sava as my favorate item
Show this item's statistics
Export Endnote File
Google Scholar
Similar articles in Google Scholar
[Jewett C.P.]'s Articles
[Mecikalski J.R.]'s Articles
百度学术
Similar articles in Baidu Scholar
[Jewett C.P.]'s Articles
[Mecikalski J.R.]'s Articles
CSDL cross search
Similar articles in CSDL Cross Search
[Jewett C.P.]‘s Articles
[Mecikalski J.R.]‘s Articles
Related Copyright Policies
Null
收藏/分享
所有评论 (0)
暂无评论
 

Items in IR are protected by copyright, with all rights reserved, unless otherwise indicated.