92nd American Meteorological Society Annual Meeting (January 22-26, 2012)

Wednesday, 25 January 2012
Construction of the New NASA Water Vapor Project-Measures (NVAP-M) Global Water Vapor Dataset
Hall E (New Orleans Convention Center )
Janice L. Bytheway, Science and Technology Corporation, Laporte, CO; and J. M. Forsythe and T. H. Vonder Haar

The NASA Water Vapor Project (NVAP) is an existing dataset that provides gridded global total column and layered water vapor blended from a variety of satellite and radiosonde observations covering 1988-2001. This dataset was produced in several phases and provided to the science community, but was never reanalyzed. A reanalysis, as well as further extension of this dataset is currently being performed under the NASA Making Earth Science Data Records for Use in Research Environments (MEaSUREs) program and will be known as NVAP-MEaSUREs (NVAP-M). This effort will result in a stable, 24-year earth system data record (ESDR) covering 1987-2010.

The reanalysis and extension of NVAP aims to make several upgrades over the existing dataset, improving both ease of use and dataset quality. In order to facilitate use for a variety of climate, weather, and hydrological applications, NVAP-M will include multiple production lines. These include a daily, 1o climate-oriented product (NVAP-M-Climate) that stresses a constant mix of data through time at a small cost to spatial and temporal resolution, while a weather-oriented component (NVAP-M-Weather) will seek to maximize use of all available data, including high quality, modern sensors (e.g. AIRS) at a time resolution of 2 4 times per day and a spatial resolution of approximately degree. An ocean-only (NVAP-M-Ocean) dataset is also available at the same spatial and temporal resolution as NVAP-M-Climate.

In order to provide the most stable, climate quality product possible, the NVAP-M-Climate dataset also takes steps to remove many of the time dependent biases present in the 1988-2001 NVAP dataset. Most of these biases are a result of algorithm and instrument changes made with each processing phase of heritage NVAP. In order to remove these biases, NVAP-M processing focuses on the use of instruments that are available continuously over the extent of the NVAP-M-Climate period of record and that have recently undergone efforts to intercalibrate duplicate instruments flying on multiple platforms. Such efforts result in a consistent, stable brightness temperature record that, when combined with careful, time-independent algorithm selection, is used to create a climate-quality record of global total column and layered water vapor.

The entire NVAP-M dataset will be available in the NASA Langley atmospheric science data center (ASDC) in early 2012; however preliminary results are currently being made available to science investigators for examination. This poster will highlight the input datasets and algorithms used to create NVAP-M, as well as some early science results demonstrating the applicability of the data to a variety of research areas.

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