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[en] Drought indices are useful for quantifying drought severity and have shown mixed success as an indicator of drought damage and biophysical dryness. While spatial downscaling of drought indicators from the climate divisional level to the county level has been conducted successfully in previous work, little research to date has attempted to “upscale” remotely sensed biophysical indicators to match the downscaled drought indices. This upscaling is important because drought damage and indices are often reported at a coarser scale than the biophysical indicators provide. This research upscales National Oceanic and Atmospheric Administration’s Advanced Very High Resolution Radiometer sensor-acquired Normalized Difference Vegetation Index (NDVI) data to produce a county-level biophysical drought index, for a five-state region of the South Central United States. The county-level NDVI is then correlated with the downscaled drought indices for assessing the degree to which the biophysical data match well-documented drought indicators. Results suggest that the Palmer Drought Severity Index and Palmer Hydrologic Drought Index are effective indicators of biophysical drought in much of the arid western part of the study area and in larger swaths of the study area in summer. In nearly all cases except for autumn months, correlations are weakest in the ecotones, with significant negative correlations in the humid eastern part of the study area. Results generally corroborate the findings of recent research that correlations between drought indices and biophysical drought vary spatially. As long-lead climate forecasts continue to improve, these results can assist environmental planners in preparing for the impacts of drought.
[en] Remote sensing measurements provide a valuable means of determining the extent of burning areas and estimating the overall distribution of the sources in time and space. The Advanced Very High Resolution Radiometer (NOAA-AVHRR) satellite is well adapted to a wide coverage of the large African savanna regions. It is necessary to watch the whole area even at times other then during the dry season, since two consecutive weeks without precipitation may be sufficient to allow the bushes to catch fire. The images examined in this chapter include the whole of West Africa - namely, within latitudes 5 degree and 14 degree N and 1 degree and 11 degree W. The study has been focused on a region that contains part of the Guinea territory, Mali, the Ivory Coast, and Burkina Faso
[en] A number of recent studies present evidence of an increasing trend in Eurasian snow cover extent (SCE) in the October snow onset period based on analysis of the National Oceanic and Atmospheric Administration (NOAA) historical satellite record. These increases are inconsistent with fall season surface temperature warming trends across the region. Using four independent snow cover data sources (surface observations, two reanalyses, satellite passive microwave retrievals) we show that the increasing SCE is attributable to an internal trend in the NOAA CDR dataset to chart relatively more October snow cover extent over the dataset overlap period (1982–2005). Adjusting the series for this shift results in closer agreement with other independent datasets, stronger correlation with continentally-averaged air temperature anomalies, and a decrease in SCE over 1982–2011 consistent with surface air temperature warming trends over the same period. (letter)
[en] Trends towards earlier greenup and increased average greenness have been widely reported in both humid and dry ecosystems. By analyzing NOAA (National Oceanic and Atmospheric Administration) AVHRR (Advanced Very High Resolution Radiometer) data from 1982 to 2007, we report complex trends in both the growing season amplitude and seasonally integrated vegetation greenness in southwestern North America and further highlight regions consistently experiencing drought stress. In particular, greenness measurements from 1982 to 2007 show an increasing trend in grasslands but a decreasing trend in shrublands. However, vegetation greenness in this period has experienced a strong cycle, increasing from 1982 to 1993 but decreasing from 1993 to 2007. The significant decrease during the last decade has reduced vegetation greenness by 6% in shrublands and 13% in grasslands (16% and 21%, respectively, in the severe drought years). The greenness cycle correlates to both annual precipitation and dry season length derived from NOAA North America Regional Reanalysis data. If drought events continue as predicted by climate models, they will exacerbate ecosystem degradation and reduce carbon uptake.
[en] On the morning of March 24, 1989, the tanker EXXON VALDEZ ran aground on Bligh Reef in Alaska's Prince William Sound. The vessel was carrying over 53 million gallons of North Slope crude oil of which almost 11 million gallons were spilled into the water. The immediately impacted area included most of the western part of the Sound, but eventually, the area expanded to include parts of Seward, Homer and Kodiak. This event constituted the worst oil spill in the history of this country, and was identified as a spill of national significance. A major response to clean up the oil by Exxon, which was closely monitored by Federal and State agencies and various interest groups, was necessary. Early in the response it was obvious t the Federal On-Scene Coordinator (FOSC) that a computer-aided management system was necessary to monitor the progress of the spill clean-up operations. This paper describes CAMEO (Computer-Aided Management of Emergency Operations) - Valdez, developed for the FOSC by the National Oceanographic and Atmospheric Administration acting in its role as the Scientific Support Coordinator (SSC)
[en] Full text: For the past 30 years, the U.S. National Oceanic and Atmospheric Administration (NOAA) has monitored all the long-lived atmospheric greenhouse gases. These global measurements have provided input to climate assessments (e.g., the quadrennial IPCC Climate Reports). Recently, efforts to make these data more useful and available have been undertaken through release of the NOAA Annual Greenhouse Gas Index (AGGI), http://www.esrl.noaa.gov/gmd/aggi. This index, based on the climate forcing properties of the long-lived greenhouse gases, was designed to enhance the connection between scientists and society by providing a normalized standard that can be easily understood and followed. Continuous greenhouse gas measurements are made at baseline climate observatories (Pt. Barrow, Alaska; Mauna Loa, Hawaii; American Samoa; and the South Pole) and weekly flask air samples are collected through a global network, including an international cooperative program for carbon gases. The gas samples are analyzed in the Boulder (NOAA/ESRL) laboratory using WMO standard reference gases prepared by ESRL. The AGGI is normalized to 1.00 in 1990, the Kyoto Climate Protocol baseline year. For the year 2006, the AGGI was 1.23, i.e. global radiative forcing by long-lived greenhouse gases has increased 23 % since 1990. The increase in carbon dioxide (CO2) alone was about 32 % over this time interval. Reductions in the growth rates of methane and the CFCs have effectively tempered the increase of CO2 since 1990. During the 1980s CO2 accounted for about 50-60 % of the annual increase in radiative forcing by long-lived greenhouse gases while today it accounts for 94 % of this increase. Preliminary values for 2007 will be included in this presentation. (author)
[en] This paper presents information on the National Oceanic and Atmospheric Administration's role in actions following oil spills. Topics include: NDAA's scientific support coordination during oil spill responses, NDAA's involvement in the Exxon Valdez spill; measures that may be taken for improved spill response; NOAA's environmental damage assessment and restoration planning activities
[en] We analyze snow cover extent (SCE) trends in the National Oceanic and Atmospheric Administration's (NOAA) northern hemisphere weekly satellite SCE data using the Mann-Kendall trend test and find that North American and Eurasian snow cover in the pan-Arctic have declined significantly in spring and summer over the period of satellite record beginning in the early 1970s. These trends are reproduced, both in trend direction and statistical significance, in reconstructions using the variable infiltration capacity (VIC) hydrological model. We find that spring and summer surface radiative and turbulent fluxes generated in VIC have strong correlations with satellite observations of SCE. We identify the role of surface energy fluxes and determine which is most responsible for the observed spring and summer SCE recession. We find that positive trends in surface net radiation (SNR) accompany most of the SCE trends, whereas modeled latent heat (LH) and sensible heat (SH) trends associated with warming on SCE mostly cancel each other, except for North America in spring, and to a lesser extent for Eurasia in summer. In spring over North America and summer in Eurasia, the SH contribution to the observed snow cover trends is substantial. The results indicate that ΔSNR is the primary energy source and ΔSH plays a secondary role in changes of SCE. Compared with ΔSNR and ΔSH, ΔLH has a minor influence on pan-Arctic snow cover changes.
[en] The Department of Energy (DOE) is moving towards Long-Term Stewardship (LTS) of many environmental restoration sites that cannot be released for unrestricted use. One aspect of information management for LTS is geospatial data archiving. This report discusses the challenges facing the DOE LTS program concerning the data management and archiving of geospatial data. It discusses challenges in using electronic media for archiving, overcoming technological obsolescence, data refreshing, data migration, and emulation. It gives an overview of existing guidance and policy and discusses what the United States Geological Service (USGS), National Oceanic and Atmospheric Administration (NOAA) and the Federal Emergency Management Agency (FEMA) are doing to archive the geospatial data that their agencies are responsible for. In the conclusion, this report provides issues for further discussion around long-term spatial data archiving
[en] A satellite placed in space is constantly affected by the space environment, resulting in various impacts from temporary faults to permanent failures depending on factors such as satellite orbit, solar and geomagnetic activities, satellite local time, and satellite construction material. Anomaly events commonly occur during periods of high geomagnetic activity that also trigger plasma variation in the low Earth orbit (LEO) environment. In this study, we diagnosed anomalies in LEO satellites using electron data from the Medium Energy Proton and Electron Detector onboard the National Oceanic and Atmospheric Administration (NOAA)-15 satellite. In addition, we analyzed the fluctuation of electron flux in association with geomagnetic disturbances 3 days before and after the anomaly day. We selected 20 LEO anomaly cases registered in the Satellite News Digest database for the years 2000–2008. Satellite local time, an important parameter for anomaly diagnosis, was determined using propagated two-line element data in the SGP4 simplified general perturbation model to calculate the longitude of the ascending node of the satellite through the position and velocity vectors. The results showed that the majority of LEO satellite anomalies are linked to low-energy electron fluxes of 30–100 keV and magnetic perturbations that had a higher correlation coefficient (~ 90%) on the day of the anomaly. The mean local time calculation for the anomaly day with respect to the nighttime migration of energetic electrons revealed that the majority of anomalies (65%) occurred on the night side of Earth during the dusk-to-dawn sector of magnetic local time. .