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During the morning (03:50:40 UTC) of 8 October 2005 a major (M w 7.6) shallow focus (26 km) earthquake struck Kashmir (Himalayan region). Its epicentre was located 10 km NNE of Muzaffarabad (USGS 2005, Magnitude 7.6-Pakistan, available online at http://earthquake.usgs.gov/eqcenter/eqinthenews/2005/usdyae/). The present manuscript is an attempt to study the development of thermal anomaly in land surface temperature (LST) preceding this earthquake. Using data from Moderate Resolution Imaging Spectroradiometer (MODIS) onboard National Aeronautics and Space Administration (NASA) Terra satellite, the daily daytime LST images have been analysed for the correlation between LST variations and Kashmir earthquakes. An evident correlation of thermal anomaly in LST that is apparently related to pre-seismic activity has been identified. An attempt has also been made to quantify the change in LST (in °C) with reference to previous day temperature values and background data (MODIS LST data from 2000-2004). A 4-8°C rise in LST to the south of the earthquake epicentre has been observed seven days before the major event. Air temperature data from two meteorological stations (Islamabad and Srinagar) also supports the observations made through MODIS LST data. The role of terrain parameters like rock types, vegetation and topography upon the spatial and temporal variations of anomalous temperature area have been studied.

In India, the Indo-Gangetic plain (part of Northern India) is invariably affected by dense fog in the winter months every year due to typical meteorological, environmental and prevailing terrain conditions. Pollution also plays an important role in the formation of fog (smoke+fog = smog) in India. Using National Oceanic and Space Administration-advanced very high resolution radiometer data the fog-affected regions in Northern India were delineated and the spatial extent of fog for the winter months of the years 2002-03, 2003-04 and 2004-05 (December-February) were studied and mapped. Forecast for future fog based on the analysis of satellite and meteorological (air temperature, relative humidity and wind speed) data was also done. The fog-affected areas were classified into maximum-fog-affected area, moderately fog-affected area and least fog-affected area. It has been found that in the winter months of the years 2002-03, 2003-04 and 2004-05, the fog-affected area in Northern India was about 867 000 km2, 625 000 km2 and 706 800 km2 respectively. The maximum fog-affected area was found to be 606 400 km2, the moderately fog-affected area was found to be 230 400 km2 and the least fog-affected area was found to be 404 500 km2. Further, based on meteorological parameters, such as temperature, humidity and wind speed along with elevation data was used to derive an approach for future fog prediction in this region.

All Sun-synchronous remote sensing satellites, during day passes always acquire images when the illumination source (i.e. Sun position) is from the SE direction. The typical solar-illumination-source-observer position creates a false topographic perception phenomenon (FTPP) in the images of any rugged terrain (e.g. Himalayas, Alps etc.). Due to the presence of FTPP, valleys appear as ridges and vice versa, especially in rugged terrain. The correction of FTPP is necessary because it creates confusion in the minds of interpreters due to inherent inverse topographic perception. This paper explains the development of a new approach to remove FTPP. It has been successfully demonstrated using an IRS-1D-LISS-III image of part of the Himalayas, which represents highly rugged terrain. In this newly developed image-processing technique; a red-green-blue (RGB) image is first transformed into intensity-hue-saturation (IHS) channels, then the original intensity channel is inverted and later retransformed back from an IHS to a RGB image. After this retransformation, the RGB image is then colour balanced with original false colour composite. The final image product is free from FTPP and also contains almost the same image information. This method is an easy and quicker method to remove FTPP in comparison to the already available methods (e.g. image rotation by 180°; creating an image negative; using an opposite illuminated shaded relief model as an intensity image during IHS to RGB retransformation) for FTPP correction. Further, this paper discusses the relative advantages of this new method in comparison to previous methods in light of image classification and lineament interpretation carried out using images with and without FTPP.

Stresses acting before an earthquake in tectonically active regions can augment the near ground temperature of the region. Such changes detected through thermal remote sensing can provide important clues about future earthquakes. A post‐earthquake analysis through NOAA‐AVHRR data showed pre‐earthquake thermal anomalies prior to the Bam earthquake on 26 December 2003 and the Dahoeieh‐Zarand earthquake on 21 February 2005 in Iran. It was observed in these earthquakes that there was short‐term temporal increase in land surface temperature (LST) of the regions around the epicenters. The rise in temperature was about 5–10°C. Further, temperature variation curves prepared from air temperature data collected from several meteorological stations around epicentres confirmed the appearance of thermal anomalies prior to several earthquakes between February and March 2005 in Iran. The thermal anomalies went away along with the earthquake events. Release of greenhouse gases from rocks due to the induced pressure befor...

On 21 May 2003, Algeria was hit by a powerful shallow focus earthquake of magnitude Mw = 6.8 (http://neic.usgs.gov/neis/bulletin/03_EVENTS/eq_030521/) at 18:44 (UTC) which led to the death of 2276 ...

Generally, almost all Sun‐synchronous satellites' orbits are designed in such a way that their equatorial crossing timings are during morning hours (normally between 09:30 to 10:30 hours). Remote s...

Digital elevation model (DEM) is a storehouse of a variety of hydrological information along with terrain characteristics. In recent years, automatic extraction of drainage network from DEM with the help of Geographical Information System (GIS) has become possible and is now being practised the world over for hydrological studies. In the present study, a comparative analysis of the drainage network derived from DEM and drainage extracted from surveyed topographical maps has been carried out. A comparative analysis based on nearest neighbour analysis on an intersection theme of two drainage networks showed that there is clustering (randomness

‘Himalaya’ means ‘abode of snow’—a term coined by the ancient pilgrims of India who travelled in these mountains. The Himalayas, home to the top 10 highest peaks in the world including the Mount Ev...