DOI: 10.1175/JCLI-D-14-00366.1
Scopus记录号: 2-s2.0-84944096411
论文题名: Precipitable water from GPS over the continental United States: Diurnal cycle, intercomparisons with NARR, and link with convective initiation
作者: Radhakrishna B. ; Fabry F. ; Braun J.J. ; Van Hove T.
刊名: Journal of Climate
ISSN: 8948755
出版年: 2015
卷: 28, 期: 7 起始页码: 2584
结束页码: 2599
语种: 英语
Scopus关键词: Atmospheric humidity
; Budget control
; Climatology
; Interpolation
; Mixing
; Moisture
; Time measurement
; Tracking (position)
; Atmospheric moisture
; Convective initiation
; Convective-scale process
; Global positioning system receivers
; Model errors
; Precipitable water vapor
; Radars/radar observations
; Short-range predictions
; Global positioning system
; climatology
; convective system
; diurnal variation
; error analysis
; GPS
; precipitable water
; prediction
; radar
; water vapor
; Great Plains
; Rocky Mountains
; United States
英文摘要: The variation of precipitable water vapor (PW) over the continental United States is examined at various time scales using spatial maps of a column-averaged mixing ratio (CAMR) that is derived from integrated column PW from both observations and reanalysis data. CAMR spatial maps are generated utilizing PW measurements obtained from a network of ground-based global positioning system (GPS) receivers and the North American Regional Reanalysis (NARR) over a time span of 4 yr (February 2009-January 2013). The effect of topography on PW is mitigated by vertically averaging the mixing ratio instead of integrating the absolute humidity. An ordinary kriging interpolation technique is used to generate spatial maps of CAMR. The observed and predicted PW derived by GPS and NARR correlate well with each other at annual and monthly scales. When focusing on its diurnal cycle, moisture peaks in the late afternoon over the Great Plains and late night over the Rockies. It is also found that atmospheric moisture within NARR generally increases in the second half of the UTC day and is adjusted significantly lower when external observations, such as radiosondes, are assimilated into the analysis system. These adjustments in the analysis introduce nonphysical offsets that are not present within the GPS-derived moisture fields. At meso-β and meso-α scales, GPS PW fields can be used as a precursor to forecast convection up to 3 h prior to initiation. As stated previously, the correlation between GPS and NARR is high (>0.98) at monthly and seasonal time scales, but there is poor correlation at time scales less than a day. This indicates that the water budget within NARR is not in proper balance over these short-term time scales. Over the continental United States, daily cycles of PW and precipitation are coupled differently in different areas. © 2015 American Meteorological Society. 资助项目: NSF, National Science Foundation
; NSF, National Science Foundation
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资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/50753
Appears in Collections: 气候变化事实与影响
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作者单位: Department of Atmospheric and Oceanic Sciences, McGill University, Montreal, QC, Canada; Constellation Observing System for Meteorology, Ionosphere, CO, United States; Climate Program Office, UCAR, Boulder, CO, United States
Recommended Citation:
Radhakrishna B.,Fabry F.,Braun J.J.,et al. Precipitable water from GPS over the continental United States: Diurnal cycle, intercomparisons with NARR, and link with convective initiation[J]. Journal of Climate,2015-01-01,28(7)