Dana Ostrenga

Tropical Rainfall Measuring Mission (TRMM) Precipitation Data and Services for Research and Applications

Precipitation is a critical component of the Earths hydrological cycle. Launched on 27 November 1997, TRMM is a joint U.S.–Japan satellite mission to provide the first detailed and comprehensive dataset of the four-dimensional distribution of rainfall and latent heating over vastly undersampled tropical and subtropical oceans and continents (40°S–40°N). Over the past 14 years, TRMM has been a major data source for meteorological, hydrological, and other research and application activities around the world. This short article describes how the NASA Goddard Earth Sciences Data and Information Services Center (GES DISC) provides TRMM archive and nearreal- time precipitation datasets and services for research and applications. TRMM data consist of orbital data from TRMM instruments at the sensors resolution, gridded data at a range of spatial and temporal resolutions, subsets, ground-based instrument data, and ancillary data. Data analysis, display, and delivery are facilitated by the following services: (1...

Developing GIOVANNI-based online prototypes to intercompare TRMM-related global gridded-precipitation products

New online prototypes have been developed to extend and enhance the previous effort by facilitating investigation of product characteristics and intercomparison of precipitation products in different algorithms as well as in different versions at different spatial scales ranging from local to global without downloading data and software. Several popular Tropical Rainfall Measuring Mission (TRMM) products and the TRMM Composite Climatology are included. In addition, users can download customized data in several popular formats for further analysis. Examples show product quality problems and differences in several monthly precipitation products. It is seen that differences in daily and monthly precipitation products are distributed unevenly in space and it is necessary to have tools such as those presented here for customized and detailed investigations. A simple time series and two area maps allow the discovery of abnormal values of 3A25 in one of the months. An example shows a V-shaped valley issue in the Version 6 3B43 time series and another example shows a sudden drop in 3A25 monthly rain rate, all of which provide important information when the products are used for long-term trend studies. Future plans include adding more products and statistical functionality in the prototypes. We developed online tools for intercomparing global precipitation products.We included 3-hourly, daily, and monthly precipitation products.We included research and near-real-time products in both Version 6 and Version 7.Basic functions help discover data quality issues and differences in products.Several data formats are available for data download and for further analysis.

MODIS data from Terra and Aqua satellites

The Moderate-resolution Imaging Spectroradiometer (MODIS) mission is entering its fourth year of successful operation and has yielded staggering amounts of data types and volumes. After the first MODIS launch in November 1999 on board the Tera satellite, a second instrument was bought to orbit on board of the Aqua satellite in May 2002. Both instruments can provide global coverage in 250-1000 m resolutions in just one day. The distribution of all MODIS data by any single NASA Distributed Active Archive Center (DAAC) is not feasible. Thus, the Goddard Earth Sciences (GES) DAAC produces Level 1A and 1B, and distributes the latter as well as the higher level of Ocean and Atmosphere products. Our goal is to give a generic picture of MODIS products and services available from GES DAAC, intended for users introducing themselves to the MODIS mission.

GES DAAC tools for accessing Terra and Aqua MODIS data

Abstract The unique position of the NASA Goddard Earth Sciences Distributed Active Archive Center (GES DAAC), as an intermediary between users and Terra and Aqua/MODIS data, let us to explore and develop tools that could help users access and manipulate data. The search and order tools include DAAC-unique extensions such as: the Web-based hierarchical ordering mechanism, the multi-product ordering system, and moderate-resolution imaging spectroradiometer (MODIS) Level 1B channel subsetting. Visualization and data manipulation tools, exemplified by HDFLook_MODIS, resulted from a joint collaboration between GES DAAC, University of Science and Technology, Lillie, and MODIS Science team; furthermore, simple interactive data language (IDL) tools were developed at GES DAAC as work aids. The key features of some of the improved tools available from the GES DAAC are described.

Online Visualization and Analysis of Global Half-Hourly Infrared Satellite Data

nfrared (IR) images (approximately 11-micron channel) recorded by satellite sensors have been widely used in weather forecasting, research, and classroom education since the Nimbus program. Unlike visible images, IR imagery can reveal cloud features without sunlight illumination; therefore, they can be used to monitor weather phenomena day and night. With geostationary satellites deployed around the globe, it is possible to monitor weather events 24/7 at a temporal resolution that polar-orbiting satellites cannot achieve at the present time. When IR data from multiple geostationary satellites are merged to form a single product--also known as a merged product--it allows for observing weather on a global scale. Its high temporal resolution (e.g., every half hour) also makes it an ideal ancillary dataset for supporting other satellite missions, such as the Tropical Rainfall Measuring Mission (TRMM), etc., by providing additional background information about weather system evolution.

Global Precipitation Measurement Mission Products and Services at the NASA GES DISC

AbstractThis article describes NASA/JAXA Global Precipitation Measurement (GPM) mission products and services at the NASA Goddard Earth Sciences (GES) Data and Information Services Center (DISC). Built on the success of the Tropical Rainfall Measuring Mission (TRMM), the next-generation GPM mission consists of new precipitation measurement instruments and a constellation of international research and operational satellites to provide improved measurements of precipitation globally. To facilitate data access, research, applications, and scientific discovery, the GES DISC has developed a variety of data services for GPM. This article is intended to guide users in choosing GPM datasets and services at the GES DISC.This article describes NASA/JAXA Global Precipitation Measurement (GPM) mission products and services at the NASA Goddard Earth Sciences (GES) Data and Information Services Center (DISC). Built on the success of the Tropical Rainfall Measuring Mission (TRMM), the next generation GPM mission consists of new precipitation measurement instruments and a constellation of international research and operational satellites to provide improved measurements of precipitation globally. To facilitate data access, research, applications, and scientific discovery, the GES DISC has developed a variety of data services for GPM. This article is intended to guide users in choosing GPM datasets and services at the GES DISC.