Long time series of daily remote sensing data (i.e. 20 years and increasing) are useful for studies of intraand interannual behaviour of surface components, such as vegetation cover and drought monitoring, and for the derivation of surface characteristics useful for climate modeling or land cover classifications. If a time series is well calibrated, data are especially valuable to detect and in...

This second part of a two-part study evaluates retrievals of aerosol optical depths, 1 and 2, in AVHRR channels 1 and 2 centered at 1=0.63 and 2=0.83 μm, and an effective Angstrom exponent, , derived therefrom as =-ln( 1/ 2)/ln( 1/ 2). The retrievals are made with the 6S radiative transfer model from four NOAA14/AVHRR datasets, collected between February 1998 May 1999 in the latitudinal belt of...

The present 2 generation aerosol retrieval algorithm over oceans at NOAA/NESDIS separately retrieves two values of aerosol optical depth, 1 and 2, from AVHRR channels 1 and 2 centered at 1=0.63 (operational) and 2=0.83 μm (experimental), respectively. From these, an effective Angstrom exponent, , related to particle size, can be derived as =-ln( 1/ 2)/ln( 1/ 2). The single-channel look-up-table...

Past studies of the NOAA AVHRR/2 and GOES I-M imagery (e.g., Setvák et al., 1996) have shown that frozen tops of deep convective storms occasionally exhibit significant increase of cloud top reflectivity when observed in the 3.7 or 3.9 μm spectral bands. Similar storm top features have been documented in the NOAA-KLM AVHRR/3 1.6 μm spectral band (Setvák et al., 2003). Consequently, cross-compar...

Recent patterns of land cover and vegetation dynamics on the Euasian continent have been linked to changes in the global carbon cycle. Our study was conducted to evaluate patterns in a 19-year record of global satellite observations of terrestrial vegetation from the Advanced Very High Resolution Radiometer (AVHRR) as a means to characterize major trends in both vegetation " greenness " and eco...

We present an algorithm for regional snow mapping that combines snow maps derived from Advanced Very High Resolution Radiometer (AVHRR) and Special Sensor Microwave/Imager (SSM/I) data. This merging algorithm combines AVHRR’s moderate spatial resolution with SSM/I’s ability to penetrate clouds and, thus, benefits from the advantages of the two sensors while minimizing their limitations. First, ...

Processing of land surface temperature from long time series of AVHRR (Advanced Very High Resolution Radiometer) requires stable algorithms, which are well characterized in terms of accuracy, precision and sensitivity. This assessment presents a comparison of four mono-window (Price 1983, Qin et al., 2001, Jiménez-Muñoz and Sobrino 2003, linear approach) and six split-window algorithms (Price 1...

This paper assesses the effect of changes in solar zenith angle (SZA) and sensor changes on reflectances in channel 1, channel 2, and normalized difference vegetation index (NDVI) from the advanced very high resolution radiometer (AVHRR) Pathfinder land data set for the period July 1981 through September 1994. First, the effect of changes in SZA on channel reflectances and NDVI is derived from ...

This study evaluates the ability to track grassland growth phenology in the Swiss Alps with NOAA-16 Advanced Very High Resolution Radiometer (AVHRR) Normalized Difference Vegetation Index (NDVI) time series. Three growth parameters from 15 alpine and subalpine grassland sites were investigated between 2001 and 2005: Melt-Out (MO), Start Of Growth (SOG), and End Of Growth (EOG).We tried to estim...