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Climatology Project (GPCP). In this paper, the impacts of assimilating temperature and humidity observations over land are evaluated in terms of analysis and forecast skills with an emphasis on the impacts on the representation of the West African monsoon in the assimilation system. The experimental design is fully described in section 2 . The impacts on the analyses and on forecasts are discussed in section 3 , where data quality control issues are also discussed. In section 4 , the humidity analysis
Climatology Project (GPCP). In this paper, the impacts of assimilating temperature and humidity observations over land are evaluated in terms of analysis and forecast skills with an emphasis on the impacts on the representation of the West African monsoon in the assimilation system. The experimental design is fully described in section 2 . The impacts on the analyses and on forecasts are discussed in section 3 , where data quality control issues are also discussed. In section 4 , the humidity analysis
and increase the number of observations that pass the quality control tests (noted as QC tests hereafter). The QC test issue will be further discussed in the following section. b. Insights into the performance of the observation operator for window channels and into the cost function change The assimilation of temperature and humidity observations depends on many conditions; one of them is a quality control test using FG departures from AMSU-A channel 4 (noted AMA4 hereafter) and AMSU-B channel 2
and increase the number of observations that pass the quality control tests (noted as QC tests hereafter). The QC test issue will be further discussed in the following section. b. Insights into the performance of the observation operator for window channels and into the cost function change The assimilation of temperature and humidity observations depends on many conditions; one of them is a quality control test using FG departures from AMSU-A channel 4 (noted AMA4 hereafter) and AMSU-B channel 2
information such as the serial numbers of the sondes, which can be decoded into the type and age of the sonde. We used this kind of information to stratify among sonde types. A further refinement using sonde age was not made here, mainly because for some sonde types the number of sondes per class would have been too small. Note that the radiosonde data used in this work are not corrected for known biases or ground calibration errors. The comparison to GPS PWV is thus representative of the quality of the
information such as the serial numbers of the sondes, which can be decoded into the type and age of the sonde. We used this kind of information to stratify among sonde types. A further refinement using sonde age was not made here, mainly because for some sonde types the number of sondes per class would have been too small. Note that the radiosonde data used in this work are not corrected for known biases or ground calibration errors. The comparison to GPS PWV is thus representative of the quality of the
in the experiment using all AMMA data and a bias correction. On the contrary, the experiment without any AMMA observations is of noticeably poorer quality. One might wish to go further in the analysis of these results by investigating which particular radiosondes or which particular sets of radiosondes provide the largest analysis changes and/or forecast improvements. It would be interesting to know, for example, if certain radiosonde stations are more valuable than others. The impact of
in the experiment using all AMMA data and a bias correction. On the contrary, the experiment without any AMMA observations is of noticeably poorer quality. One might wish to go further in the analysis of these results by investigating which particular radiosondes or which particular sets of radiosondes provide the largest analysis changes and/or forecast improvements. It would be interesting to know, for example, if certain radiosonde stations are more valuable than others. The impact of
data are collected every 6 h and the station is located at the airport in Niamey. Uniquely in this project, the microclimate conditions within the roof space of a traditionally constructed woven grass hut were monitored. It is within this microclimatic space that mosquitoes that have taken a human blood meal and have potentially ingested malaria parasites, develop the next stage in the parasite’s life cycle. The microclimate also controls the proportion of the mosquitoes that survive, long enough
data are collected every 6 h and the station is located at the airport in Niamey. Uniquely in this project, the microclimate conditions within the roof space of a traditionally constructed woven grass hut were monitored. It is within this microclimatic space that mosquitoes that have taken a human blood meal and have potentially ingested malaria parasites, develop the next stage in the parasite’s life cycle. The microclimate also controls the proportion of the mosquitoes that survive, long enough
performed by taking a maximum of four vertical measurements between two model levels. Namely, if the pressure difference between consecutive sounding levels was less than one-fourth of the model vertical resolution, then that sounding level was discarded. The thinned data profile was checked for consistency with the high-resolution vertical profile. The second experiment is the control experiment, which uses only data received via GTS from stations that were reliably reporting to the GTS in 2005, that
performed by taking a maximum of four vertical measurements between two model levels. Namely, if the pressure difference between consecutive sounding levels was less than one-fourth of the model vertical resolution, then that sounding level was discarded. The thinned data profile was checked for consistency with the high-resolution vertical profile. The second experiment is the control experiment, which uses only data received via GTS from stations that were reliably reporting to the GTS in 2005, that
Africa. The modeling system is briefly introduced in the following section. As the focus is West Africa, the analysis presented here restricts itself to the main summer monsoon period. The validation uses a set of 49 hindcast ensembles conducted at ECMWF for the years 1960–2008, with additional attention paid to 2006, the year of the AMMA SOP. 2. Model and data The Seasonal Forecast System that is evaluated here is closely related to the other ECMWF forecast systems of a single deterministic
Africa. The modeling system is briefly introduced in the following section. As the focus is West Africa, the analysis presented here restricts itself to the main summer monsoon period. The validation uses a set of 49 hindcast ensembles conducted at ECMWF for the years 1960–2008, with additional attention paid to 2006, the year of the AMMA SOP. 2. Model and data The Seasonal Forecast System that is evaluated here is closely related to the other ECMWF forecast systems of a single deterministic
) . In the present case, it is also shown that an explicit representation of moist convection favors stronger interactions among surface and atmospheric processes at smaller scales, and is associated with both a drier atmosphere and lower evapotranspiration rates. The spectacular enhancement of sounding data available in summer 2006 during the largest AMMA field campaign ( Parker et al. 2008 ) made it possible to generate analyses and reanalyses ( Agustí-Panareda et al. 2009 ) of a quality that was
) . In the present case, it is also shown that an explicit representation of moist convection favors stronger interactions among surface and atmospheric processes at smaller scales, and is associated with both a drier atmosphere and lower evapotranspiration rates. The spectacular enhancement of sounding data available in summer 2006 during the largest AMMA field campaign ( Parker et al. 2008 ) made it possible to generate analyses and reanalyses ( Agustí-Panareda et al. 2009 ) of a quality that was