Interpretation Of Satellite Data Research Articles

Characterization and Evaluation of Natural Resources for Land Use Diversification Planning: A Case Study in a Block of Meghalaya Using RS & GIS Technique

Characterization and evaluation of land resources of Mawryngkneng block was carried out using IRS-P6 LISS III and LISS-IV data. Five major physiographic units namely structural hills, denudational hills, plateau and intermontane valley were identified. Visual interpretation of satellite data indicated that 32.2% of the total geographical area (TGA) is under dense forest followed by wastelands (28.8%), open forest (16.1%), cultivated area (13.6%), built up area (8.2%) and water body (0.9%). Ten soil series were tentatively identified and the soils belonged to 2 orders (Ultisols and Alfisols), 3 sub orders (Udult, Udalf and Humult), 6 great groups, 8 sub groups. The soils are moderately acidic, deep to very deep and texture varies from sandy clay loam to clay. The soils are very rich in organic carbon. The availability of nitrogen is medium to high and phosphorus availability is low to medium whereas potassium availability is low in the entire study area. The soils were grouped into land capability class II & III and the soils were moderately to marginally suitable for orange and marginally suitable for pine apple. An action plan with suggested land use and interventions has been prepared by using all land resource information generated under the study. The action plan includes areas for afforestation, intensive cultivation in the existing cropped areas with soil conservation measures like mulching, zero tillage etc. and orange and pine apple plantation in open scrub lands which are cultivable wastelands. This might help the farmers and the planner in better management of land resources for sustained productivity.

Satellite-based virtual buoy system to monitor coastal water quality

There is a pressing need to assess coastal and estuarine water quality state and anomaly events to facilitate coastal management, but such a need is hindered by lack of resources to conduct frequent ship-based or buoy-based measurements. Here, we established a virtual buoy system (VBS) to facilitate satellite data visualization and interpretation of water quality assessment. The VBS is based on a virtual antenna system (VAS) that obtains low-level satellite data and generates higher-level data products using both National Aeronautics and Space Administration standard algorithms and regionally customized algorithms in near real time. The VB stations are predefined and carefully chosen to cover water quality gradients in estuaries and coastal waters, where multiyear time series at monthly and weekly intervals are extracted for the following parameters: sea surface temperature (°C), chlorophyll-a concentration (mg m −3 ), turbidity (NTU), diffuse light attenuation at 490 nm [K d (490) , m −1 ] or secchi disk depth (m), absorption coefficient of colored dissolved organic matter (m −1 ), and bottom available light (%). The time-series data are updated routinely and provided in both ASCII and graphical formats via a user-friendly web interface where all information is available to the user through a simple click. The VAS and VBS also provide necessary infrastructure to implement peer-reviewed regional algorithms to generate and share improved water quality data products with the user community.

Fully Engaging Students in the Remote Sensing Process Through Field Experience

Field data collection is often crucial to the success of investigations based upon remotely sensed data. Students of environmental remote sensing typically learn about the discipline through classroom lectures, a textbook, and computer laboratory sessions focused on the interpretation and processing of aircraft and satellite data. The importance of field validation of the data and products derived from them is rarely demonstrated through a field experience. Exercises designed for two separate courses are described: one at the undergraduate level and one at the graduate level. Through the comparison of pre- and post-test results, it was concluded that efforts to engage students in remote sensing data collection significantly benefits their understanding of the physical basis of environmental remote sensing (radiation/Earth surface interaction).

A Comparative Analysis and Evaluation of Neka River Basin Deforested Land from 1977-2006 using MSS, TM and ETM Satellite Images

The main objective of this study is to find out the loss of forest area through analyzing it in different periods. In general, deforestation can be regarded as one of the most important elements in LULC and the scenario of global changes is taking place around the world. Therefore, it is worth assessing its trend and the rate at which it is taking place now. These changes will play a significant role in bringing about some changes in regional climate and accordingly on biodiversity. The loss of forest in Iran is going on since 1960 onwards in the Neka river Basin. The estimation of forest loss was not reported to be done by using Satellite data. The changes occurring in forest cover were reported by a series of four satellite images in different time intervals by using Remote Sensing (RS) and GIS such as Land satMSS of 1977, Land satTM of1987, ETM 2001 and ETM+ 2006. The forest covers were analyzed and maps from four temporal satellite datasets were prepared. Based on 1977, 1987, 2001 and 2006 satellite data interpretation, the forest cover was converted to geospatial database. According to the results obtained from these images, there was a decrease in forest area (7096.63), productive forest area, as well as degraded forest area. However, the total forest area showed a decrease in the first period (1977-1987) although an increase was reported again during the second period (1987-2001) to 2418.82 hectares (3.5% of the study area), this trend continued even between 2001-2006 and the mixed forest cover increased by856.08 hectares (1.31%). This increase was due to few hectares of mixed forest area was converted into manmade forest.

Airborne Remote Sensing of Coastal Features and Processes: An Overview

Klemas, V., 2013. Airborne remote sensing of coastal features and processes: an overview. Coastal ecosystems tend to be spatially complex and exhibit high temporal variability. Observing them requires the ability to monitor their biophysical features and controlling processes at high spatial and temporal resolutions, which can be provided by airborne remote sensors. High-resolution satellite data are now also available, yet the finer resolution and frequent, flexible overflights offered by airborne sensors can be more effective in a range of coastal research and management applications, such as wetlands mapping, coastal bathymetry, and tracking coastal plumes, salinity gradients, tidal fronts, and oil slicks. The airborne imagery is also useful for the interpretation of satellite data. This article reviews estuarine and coastal remote sensing applications that require the high spatial and temporal resolutions provided by airborne sensors.

Comparison of primary productivity estimates in the Baltic Sea based on the DESAMBEM algorithm with estimates based on other similar algorithms

The quasi-synoptic view available from satellites has been broadly used in recent years to observe in near-real time the large-scale dynamics of marine ecosystems and to estimate primary productivity in the world ocean. However, the standard global NASA ocean colour algorithms generally do not produce good results in the Baltic Sea. In this paper, we compare the ability of seven algorithms to estimate depth-integrated daily primary production (PP, mg C m−2) in the Baltic Sea. All the algorithms use surface chlorophyll concentration, sea surface temperature, photosynthetic available radiation, latitude, longitude and day of the year as input data. Algorithm-derived PP is then compared with PP estimates obtained from 14C uptake measurements. The results indicate that the best agreement between the modelled and measured PP in the Baltic Sea is obtained with the DESAMBEM algorithm. This result supports the notion that a regional approach should be used in the interpretation of ocean colour satellite data in the Baltic Sea.

Using the optical and radar satellite images for the analysis of ecological conditions in the marine environment

Considered are the possibilities for detecting the zones of ecological problems of marine environment using the ocean color sensors data and the radar images. Presented are the peculiarities of satellite data interpretation and the experimental results indicating the spatial and temporal distribution of biogenic slicks and chlorophyll-a concentration as the indicators of ecological conditions in the marine environment. Proposed is the multiparameter correlation graph displaying the relationship between the ecological factors significant for studying the anthropogenic eutrophication.

Satellite data assimilation and estimation of a 3D coastal sediment transport model using error-subspace emulators

This paper describes sequential assimilation of data into a three-dimensional coastal ocean model using fast and cheap statistical surrogates of the model (emulators). The model simulates resuspension and deposition of fine sediments in a macro-tidal environment of the Fitzroy Estuary and Keppel Bay, North-East Australian coast. The assimilation algorithm was applied first to synthetic observations produced by a twin model run, and then with real data obtained from satellite observation. The latter are derived from remote sensing algorithms customised to the study region. The main objective of simulations was to test the data assimilation scheme using synthetic observations and identify potential issues and challenges when assimilating real data sets. The assimilation algorithm proved capable of substantially reducing a prior uncertainty of the model for both the scenario with the synthetic observations and the scenario with the satellite data. Significant remaining error in western Keppel Bay after assimilating satellite data is diagnostic of an underlying error in the system conceptualisation – in other words, it indicates that the primary source of error is not in the parameter values specified, but in the model structure, in the interpretation of satellite data or in the other input data. The results of our study show the utility of the developed technique for the data assimilation into the three-dimensional sediment transport model of the Fitzroy estuary and Keppel Bay. More research is required to understand the capacity of this technique to generalise to other models and regions.

THE 2005 AND 2010 AMAZONIAN DROUGHTS AS SEEN BY MODIS

Abstract. During this decade, the Amazon region in South America has suffered two severe droughts in the short span of five years ––2005 and 2010. The 2005 drought, dubbed a once-in-a-century drought, has been the focus and driver of many studies on the drought sensitivity of Amazon forests. These studies present a complex, and sometimes contradictory, picture of how these forests have responded to the 2005 drought. In particular, Saleska et al. (Science, 2007) reported excessive greening of the forests in response to the drought. But, this has now been proven by Samanta et al. (GRL, 2010) to be artifact of atmospheric-corruption of the satellite data analyzed by Saleska et al. (2007). In the first part of my talk, I will focus on the Saleska et al. and Samanta et al. studies. On the heels of the 2005 drought, came an even stronger drought in 2010, as indicated by record low river levels in the 109 years of bookkeeping. How have the forests responded to this record-breaking drought? Did they green-up or brown-down? I will address this in the second part of my talk. The objective of my talk will be to emphasize the care required in analysis and interpretation of satellite data.

Gas Hydrates Accumulations on the South Shetland Continental Margin: New Detection Possibilities

The results of investigations in 2006–2010 for hydrocarbon and gas hydrates on the Antarctic Peninsula continental margin are given. In 2004 and 2006, the marine geoelectric researches by methods of forming a short-pulsed electromagnetic field (FSPEF) and vertical electric-resonance sounding (VERS) had been conducted in this region. The “deposit” type anomaly was mapped by FSPEF survey, and anomalous polarized layers of “hydrocarbon deposit” type were chosen by VERS sounding within this anomaly on Antarctic margin in the region of UAS “Academician Vernadsky.” Anomalous zones of “gas hydrate deposit” type were detected on the South Shetland margin due to the special technology of satellite data processing and interpretation using. These results confirm the high gas hydrates potential of the West Antarctica region. Some practical results of the experimental approbation of these original technologies for the “direct” prospecting and exploration of hydrocarbon (HC) and gas hydrates accumulations in different oil-and-gas bearing basins of Russia and Gulf of Mexico are proposed. The integration of satellite data processing and materials of FSPEF-VERS methods enable improving their efficiency for different geological and geophysical problems solving.

ГЕОДИНАМІКА

The results of experimental approbation of geoelectric methods of forming short-pulsed electromagnetic field (FSPEF) vertical electric-resonance sounding (VERS) and the technology of satellite data processing and interpretation for the "direct" prospecting the ore minerals and water-bearing reservoirs are analyzed.

Water Balance Study and Irrigation Strategies for Sustainable Management of a Tropical Ethiopian Lake: A Case Study of Lake Alemaya

Lake Alemaya in the Ethiopian Highlands has historically provided the surrounding area with water for domestic use, irrigation, and livestock and has served as a local fishery tank. Increasing irrigation and domestic water use, change in the local climate and changes in the surrounding land cover are believed to be the causes of Lake Alemaya’s demise. Expansion of major irrigated crops in particular chat (Catha Edulis), potato and vegetables and non-judicious use of irrigation water in the Lake Alemaya watershed led to presumption that irrigation is partly responsible for the withdrawal of large quantity of water from the lake. Thus, water balance study of Lake Alemaya was carried out under presumed scenarios in order to study the possible trends and fluctuations of the lake water level in response to proposed scenarios. Further, it is essential to study the irrigation performance for developing optimal irrigation schedules in the study area to make the best use of available water for long term sustainability of the water resources of Lake Alemaya. It was identified that expansion of the irrigated area in general and chat cultivation in particular in the study area have been the key to sustainable management of lake water, hence its expansion during the past 37 years (1965–2002) was studied through interpretation of satellite data. Subsequently, performance evaluation of the small-scale irrigation practices for major irrigated crops was carried out. Optimal irrigation schedules for different crop seasons were also developed for these irrigated crops using CROPWAT software. It was found that chat area increased from 190 ha in 1996 to nearly 330 ha in 2002. Further, it was observed that 43% surface area of the lake has reduced within a span of 37 years. Overall, maximum irrigation intensity of chat, potato and vegetables is observed during the first irrigation season of the crop calendar. Particularly, in case of chat, irrigation performance indicators such as Relative Water Supply (RWS), Relative Irrigation Supply (RIS), Depleted Fraction (DF) and Overall Consumed Ratio (OCR) values indicated poor performance of irrigation practices. From the analysis, it was found that the application of a fixed irrigation depth and fixed irrigation interval combinations of (25 mm—25 day), (20 mm—20 day), or (20 mm—25 day) are recommended for chat in the study area. Optimal irrigation schedules were decided on the basis of combination of irrigation interval and depth that results in low loss of irrigation water with reasonable yield reduction. Thus, determination of appropriate water management strategy can ensure proper utilization of the available water resources and improve the water application efficiency of the small-scale irrigation practices around Lake Alemaya, Ethiopia.

A remote sensing derived upper ocean heat content dataset for the equatorial atlantic: comparison with pirata project data

In this work, nine years (1998-2006) of Sea Level Anomalies (SLA) from multimission altimeter data distributed by Archiving Validation and Interpretation of Satellite Data in Oceanography (AVISO) were combined with Sea Surface Temperature (SST) data from the TRMM Microwave Imager and climatological subsurface data from World Ocean Atlas 2001 (VVOA01) through a reduced gravity model, as well as a statistical model, to generate maps of Upper Layer Heat content (ULH) for the Equatorial Atlantic. In order to validate the ULH estimates, we perform a comparison with an independent in situ data from Prediction and Research Moored Array in the Tropical Atlantic (PIRATA). There is a very good match between the ULH anomalies derived from remote sensing and from PIRATA moorings. The best correlations are for the northwest Equatorial Atlantic PIRATA buoys, while the worst correlations are for the southeastern Equatorial Atlantic sites. We believe that using the most recent World Ocean Atlas 2009 (WOA09), which already incorporates the PIRATA dataset, could further improve the present method.

Assessment of spatial and temporal dynamics of tropical forest cover: A case study in Malkangiri district of Orissa, India

Tropical forests have been recognized as having global conservation importance. However, they are being rapidly destroyed in many regions of the world. Regular monitoring of forests is necessary for an adaptive management approach and the successful implementation of ecosystem management. The present study analyses the temporal changes in forest ecosystem structure in tribal dominated Malkangiri district of Orissa, India, during 1973–2004 period based on digitized forest cover maps using geographic information system (GIS) and interpretation of satellite data. Three satellite images Landsat MSS (1973), Landsat TM (1990) and IRS P6 LISS III (2004) were used to determine changes. Six land cover types were delineated which includes dense forest, open forest, scrub land, agriculture, barren land and water body. Different forest types were also demarcated within forest class for better understanding the degradation pattern in each forest types. The results showed that there was a net decrease of 475.7 km2 forest cover (rate of deforestation = 2.34) from 1973 to 1990 and 402.3 km2 (rate of deforestation = 2.27) from 1990 to 2004. Forest cover has changed over time depending on a few factors such as large-scale deforestation, shifting cultivation, dam and road construction, unregulated management actions, and social pressure. A significant increase of 1222.8 km2 agriculture area (1973–2004) clearly indicated the conversion of forest cover to agricultural land. These alterations had resulted in significant environmental consequences, including decline in forest cover, soil erosion, and loss of biodiversity. There is an urgent need for rational management of the remaining forest for it to be able to survive beyond next decades. Particular attention must be paid to tropical forests, which are rapidly being deforested.

Analyzing the Proposals of FAP 8B Project of Dhaka and Present Context of Retention Pond Areas and Canals

After the devastating flood of 1988, the government adopted a program under FAP-8B to protect Dhaka city from flooding. It included two-part coordinated action plan, namely FAP-8A & FAP-8B. The project “FAP-8B” covered 136.5 sq. km of western part of Dhaka and the primary objective was to provide a relatively flood free and secured living environment. Proposals of FAP-8B focused on construction of retention ponds with pumping facilities and rehabilitation of 21 major natural canals having a total length of 78.6 km. The FAP-8B project started in 1991 and completed by 1997. This paper studied the land use changes within the designated retention pond areas and canals in the FAP-8B area through interpretation of satellite images and data on physical features. The study used satellite images of the years 1989, 1999, 2004, 2007, RS (Revenue Survey) maps and land use maps of Detailed Area Plan (DAP). Findings of the study revealed that proposed 4.5% retention pond areas of FAP-8B has been encroached by various land use activities and at present only 1.79% retention pond areas are left. Encroachments of natural canals are also alarming. It is found that 34% area of 13 natural canals has been filled up by developers, private individuals and others. Between 1989 and 2007, area of wetland was reduced from 22.15% to 12.17% in the west Dhaka. The results suggest that without government intervention to save the remaining retention areas and canals, it would be difficult to uphold the flood control functions of FAP-8B project. Journal of Bangladesh Institute of Planners, Vol. 3, Dec 2010, pp. 89-102

Palaeochannel detection and aquifer performance assessment in Mendha River catchment, Western India

Summary The state of Rajasthan is one of the regions of India that has scarce water resources. In the desertic terrain of the state, there are large numbers of palaeochannels that are considered to be potential aquifers for the region. However, detection and delineation of these palaeochannels is a challenging task because most of the surface signatures are obliterated by recent alluvial cover or the land use pattern. In the present study, multi-resolution, multi-temporal satellite data products from a suite of satellites such as IRS-1D, and Landsat MSS were digitally enhanced and used to detect the palaeochannels. One of the prominent palaeochannels delineated was investigated to evaluate aquifer parameters by conducting pumping tests. Pumping test data from aquifers surrounding the palaeochannel were also collected and compared in order to assess the relative groundwater prospects of the aquifer. An integrated approach which included interpretation of multi-temporal satellite data, slope variation, drainage, geomorphology and field investigation has helped to detect several palaeochannels in the study area. The study also confirms that the palaeochannel aquifer has more potential than the surrounding aquifers.

Monitoring Vegetation Phenological Cycles in Two Different Semi-Arid Environmental Settings Using a Ground-Based NDVI System: A Potential Approach to Improve Satellite Data Interpretation

In semi-arid environmental settings with sparse canopy covers, obtaining remotely sensed information on soil and vegetative growth characteristics at finer spatial and temporal scales than most satellite platforms is crucial for validating and interpreting satellite data sets. In this study, we used a ground-based NDVI system to provide continuous time series analysis of individual shrub species and soil surface characteristics in two different semi-arid environmental settings located in the Great Basin (NV, USA). The NDVI system was a dual channel SKR-1800 radiometer that simultaneously measured incident solar radiation and upward reflectance in two broadband red and near-infrared channels comparable to Landsat-5 TM band 3 and band 4, respectively. The two study sites identified as Spring Valley 1 site (SV1) and Snake Valley 1 site (SNK1) were chosen for having different species composition, soil texture and percent canopy cover. NDVI time-series of greasewood (Sarcobatus vermiculatus) from the SV1 site allowed for clear distinction between the main phenological stages of the entire growing season during the period from January to November, 2007. NDVI time series values were significantly different between sagebrush (Artemisia tridentata) and rabbitbrush (Chrysothamnus viscidiflorus) at SV1 as well as between the two bare soil types at the two sites. Greasewood NDVI from the SNK1 site produced significant correlations with chlorophyll index (r = 0.97), leaf area index (r = 0.98) and leaf xylem water potential (r = 0.93). Whereas greasewood NDVI from the SV1 site produced lower correlations (r = 0.89, r = 0.73), or non significant correlations (r = 0.32) with the same parameters, respectively. Total percent cover was estimated at 17.5% for SV1 and at 63% for SNK1. Results from this study indicated the potential capabilities of using this ground-based NDVI system to extract spatial and temporal details of soil and vegetation optical properties not possible with satellite derived NDVI.

Pan-African dextral transpressive duplex and flower structure in the Central Eastern Desert of Egypt

The NE–SW trending Mubarak shear belt in the Central Eastern Desert (CED) of Egypt records the structural features of a transpression regime. Structural interpretation of satellite data and field observations indicates the presence of two episodes of deformation. The less dominant D 1 deformation is related to sinistral movement along NW–SE trending Wadi Abu Dabbab shear zone and formation of F 1 tight to isoclinal non-cylindrical folds and thrust fan as a consequence of transpression. The thrust fan includes ESE- to SE-dipping thrusts in the ophiolitic mélange and S- to SSW-dipping thrusts in the northern part of the metagabbro–diorite complex. The transpression-related sinistral shear regime is superimposed by the dominant D 2 dextral transpression along NE–SW trending Wadi El-Umra shear zone. This dextral shearing is characterized by development of NNE- to NE-trending S 2 cleavage, strike-slip duplex, NNE- and NE-trending F 2 folds, and NNW-directed thrusts. These two events represent a single progressive phase associated with sinistral transpressional deformation, which is related to a younger E–W shortening event. E–W directed shortening is due to oblique convergence between East and West Gondwana along the Mozambique belt. Transpressional structures in the NE–SW trending Mubarak–Barramiya shear belt indicate highly oblique convergence leading to wrench-dominated dextral transpression and development of a major flower structure between Wadi Mubarak and Hafafit dome occupying the whole width of the CED.

О новых перспективах нефтегазоносности структур дна Западной Антарктики

The results of investigations in 2006-2010 for oil and gas in the Antarctic Peninsular region are given. In 2004 and 2006, the geoelectric research by methods of forming a short-pulsed electromagnetic field (FSPEF) and vertical electric-resonance sounding (VERS) have been conducted from shipboard in this region. The "deposit" type anomaly was mapped by FSPEF survey, and anomalous polarized layers of "hydrocarbon deposit" type were chosen by VERS sounding within this anomaly on Antarctic margin. The anomalous zones of “oil deposit” type were mapped also on Antarctic Peninsular margin in the region of UAS "Academician Vernadsky" and anomalous zones of “gas hydrate deposit” type were revealed at the South Shetland margin. The investigation results confirm the high oil and gas potential of the West Antarctica region. The special technology of satellite data processing and interpretation can be used for the hydrocarbon accumulations prospecting and exploration in remote regions such as Antarctic and Arctic areas.

Revisiting sites of the South Pole Queen Maud Land Traverses in East Antarctica: Accumulation data from shallow firn cores

Ground‐based accumulation measurements are scarce on the high East Antarctic plateau, but highly necessary for model validation and the interpretation of satellite data for the determination of Antarctic mass balance. Here, we present accumulation results obtained from four shallow firn cores drilled in the Antarctic summer season 2007/2008. The cores were drilled along the first leg of the Norwegian‐US IPY traverse through East Antarctica, visiting sites like Plateau Station and Pole of Relative Inaccessibility that have been covered by the South Pole Queen Maud Land Traverses (SPQMLT) in the 1960s. Accumulation has been determined from volcanic chronology established from the conductivity records measured by dielectric profiling (DEP). The Tambora 1815/unknown 1809 double peak is clearly visible in the conductivity data and serves as a reliable time marker. Accumulation rates averaged over the period 1815–2007 are in the range of 16 to 32 kg m−2 a−1, somewhat lower than expected from the SPQMLT data. The spatial pattern is mainly influenced by elevation and continentality. Three of the firn cores show a decrease of more than 20% in accumulation for the time period 1815–2007 in relation to accumulation rates during the period 1641–1815. The spatial representativity of the firn cores is assessed by ground‐penetrating radar, showing a rather smoothly layered pattern around the drill sites. Validation of the DEP results is utilized by comparison with chemistry data, proving the validity of the DEP method for dating firn cores. The results help understanding the status of the East Antarctic ice sheet and will be important for e.g. future model‐derived estimates of the mass balance of Antarctica.