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1. Introduction The history of environmental satellite measurements now spans several decades, which is relatively sufficient to form a climate data record (CDR) for climate-related studies. Based on the National Research Council’s definition ( NRC 2004 ), a CDR is a time series of measurements of sufficient length, consistency, and continuity to determine climate variability and change. The Special Sensor Microwave Imager (SSM/I) series provide one of the longest time series of satellite
1. Introduction The history of environmental satellite measurements now spans several decades, which is relatively sufficient to form a climate data record (CDR) for climate-related studies. Based on the National Research Council’s definition ( NRC 2004 ), a CDR is a time series of measurements of sufficient length, consistency, and continuity to determine climate variability and change. The Special Sensor Microwave Imager (SSM/I) series provide one of the longest time series of satellite
same procedure was followed with the F-10 , F-14 , and F-15 satellites (descending orbit varying from 0800 to 1000 LST) to create a late-morning time series for the same period (1992–2007). This dual-satellite dataset offers an excellent opportunity to achieve a better temporal sampling, as well as sampling at a different time of the day, critical to capture a portion of the diurnal variability of precipitation. a. The statistical-based quality control procedure The statistical QC scheme is
same procedure was followed with the F-10 , F-14 , and F-15 satellites (descending orbit varying from 0800 to 1000 LST) to create a late-morning time series for the same period (1992–2007). This dual-satellite dataset offers an excellent opportunity to achieve a better temporal sampling, as well as sampling at a different time of the day, critical to capture a portion of the diurnal variability of precipitation. a. The statistical-based quality control procedure The statistical QC scheme is
1. Introduction Oceanic precipitation is a major component of the hydrological cycle and climate processes. The oceans cover about 70% of the earth’s surface where most of the freshwater exchange occurs. The major driving force for atmospheric circulations also comes from the latent heat release associated with precipitation processes. Global precipitation is linked to the surface energy budget through evaporation, which occurs mostly over oceans. The understanding of trends and variability of
1. Introduction Oceanic precipitation is a major component of the hydrological cycle and climate processes. The oceans cover about 70% of the earth’s surface where most of the freshwater exchange occurs. The major driving force for atmospheric circulations also comes from the latent heat release associated with precipitation processes. Global precipitation is linked to the surface energy budget through evaporation, which occurs mostly over oceans. The understanding of trends and variability of
, GPCP V2 and TRMM 3B43. Additionally, the input parameters for the evaporation retrieval, wind, and sea–air humidity difference are assessed. All used time series have a temporal overlap with HOAPS-3 of more than one decade from January 1992 to December 2005. The resulting comparison period of 14 years is an advance over previous studies that are mostly limited to substantially shorter time periods. However, some of these estimates are not fully independent as input data from the same observations
, GPCP V2 and TRMM 3B43. Additionally, the input parameters for the evaporation retrieval, wind, and sea–air humidity difference are assessed. All used time series have a temporal overlap with HOAPS-3 of more than one decade from January 1992 to December 2005. The resulting comparison period of 14 years is an advance over previous studies that are mostly limited to substantially shorter time periods. However, some of these estimates are not fully independent as input data from the same observations
within this quasi-global region are due to the satellite orbit height, which is about 1200 km at the apogee in the Northern Hemisphere and 600 km at the perigee in the Southern Hemisphere. This means that the sensor spatial resolution will change along the elliptical orbit, being larger at the apogee and smaller at the perigee. In this paper we did not consider this field-of-view variability that is inherent when exploiting elliptical orbits and might be used to regionalize the mission products. On
within this quasi-global region are due to the satellite orbit height, which is about 1200 km at the apogee in the Northern Hemisphere and 600 km at the perigee in the Southern Hemisphere. This means that the sensor spatial resolution will change along the elliptical orbit, being larger at the apogee and smaller at the perigee. In this paper we did not consider this field-of-view variability that is inherent when exploiting elliptical orbits and might be used to regionalize the mission products. On
. Kiehl , 2003 : Mineral aerosol and cloud interactions. Geophys. Res. Lett. , 30 , 1475 . doi:10.1029/2002GL016762 . McCollum , J. R. , A. Gruber , and M. B. Ba , 2000 : Discrepancy between gauges and satellite estimates of rainfall in equatorial Africa. J. Appl. Meteor. , 39 , 666 – 679 . Nicholson , S. E. , 2000 : The nature of rainfall variability over Africa on time scales of decades to millennia. Global Planet. Change , 26 , 137 – 158 . Okamoto , K. , T. Iguchi
. Kiehl , 2003 : Mineral aerosol and cloud interactions. Geophys. Res. Lett. , 30 , 1475 . doi:10.1029/2002GL016762 . McCollum , J. R. , A. Gruber , and M. B. Ba , 2000 : Discrepancy between gauges and satellite estimates of rainfall in equatorial Africa. J. Appl. Meteor. , 39 , 666 – 679 . Nicholson , S. E. , 2000 : The nature of rainfall variability over Africa on time scales of decades to millennia. Global Planet. Change , 26 , 137 – 158 . Okamoto , K. , T. Iguchi
prepare for the Global Precipitation Measurement (GPM) mission that is scheduled to launch early in the next decade and will include coincident active and passive measurements at higher latitudes. Relative to passive-only microwave snowfall observations, active spaceborne observations offer the distinct advantage of providing high-resolution information about the vertical structure of precipitation. However, active satellite-based global snowfall observations are extremely limited. The Tropical
prepare for the Global Precipitation Measurement (GPM) mission that is scheduled to launch early in the next decade and will include coincident active and passive measurements at higher latitudes. Relative to passive-only microwave snowfall observations, active spaceborne observations offer the distinct advantage of providing high-resolution information about the vertical structure of precipitation. However, active satellite-based global snowfall observations are extremely limited. The Tropical
1. Introduction Over the past decade, a number of precipitation products with high spatial and temporal resolution and near-global coverage have been developed. These products combine precipitation information from multiple sensors and multiple algorithms to produce estimates of rainfall over the globe at spatial resolutions of 0.25° latitude/longitude (or finer) and 3-h temporal resolution (or less). Because these products are constructed from satellite data, they supply crucial rainfall
1. Introduction Over the past decade, a number of precipitation products with high spatial and temporal resolution and near-global coverage have been developed. These products combine precipitation information from multiple sensors and multiple algorithms to produce estimates of rainfall over the globe at spatial resolutions of 0.25° latitude/longitude (or finer) and 3-h temporal resolution (or less). Because these products are constructed from satellite data, they supply crucial rainfall
1. Introduction With continuous improvement over the past three decades, satellite precipitation estimation techniques now offer the means to map both occurrence and distribution of global rain rate. With the deployment of the first Special Sensor Microwave Imager (SSM/I; Hollinger et al. 1987 ), passive microwave (PMW) remote sensing of precipitation was recognized as the most reliable source of instantaneous precipitation estimates ( Adler et al. 2001 ; Ebert et al. 1996 ). To date, all
1. Introduction With continuous improvement over the past three decades, satellite precipitation estimation techniques now offer the means to map both occurrence and distribution of global rain rate. With the deployment of the first Special Sensor Microwave Imager (SSM/I; Hollinger et al. 1987 ), passive microwave (PMW) remote sensing of precipitation was recognized as the most reliable source of instantaneous precipitation estimates ( Adler et al. 2001 ; Ebert et al. 1996 ). To date, all
1. Introduction Precipitation affects all aspects of human life. However, despite its great importance, the correct spatiotemporal detection and quantification of this key factor of the global water cycle is still associated with large uncertainties. This is mainly due to the high spatial and temporal variability of precipitation distribution. In this context, optical sensors aboard geostationary weather satellites provide information about rainfall distribution in a high spatial and temporal
1. Introduction Precipitation affects all aspects of human life. However, despite its great importance, the correct spatiotemporal detection and quantification of this key factor of the global water cycle is still associated with large uncertainties. This is mainly due to the high spatial and temporal variability of precipitation distribution. In this context, optical sensors aboard geostationary weather satellites provide information about rainfall distribution in a high spatial and temporal
