Assessment of different topographic corrections in MODIS data for mapping effective snow covered areas in mountainous terrain

2008-06-05
Topography and its derivatives (altitude, slope and aspect) have an effect on satellite-measured radiances. For mountainous areas the sun zenith and azimuth angles, as well as direction of observation relative to these are more limiting factors. In this paper four topographic normalization methods were used to correct the reflectance values of medium spatial resolution satellite data, namely MODIS. The performance of the topographic normalization methods is examined for snow covered areas of the study area located in the eastern part of Turkey. Modeling of snow-covered area in the mountainous regions of Eastern Turkey has significant importance in order to forecast snowmelt discharge especially for optimum use of water in energy production, flood control, irrigation and reservoir operation optimization. MOD09GKM data, which have the land surface reflectance having atmospheric correction, digital elevation model (DEM) and the geo-location files (MOD03) were used. It is obtained that statistical empirical correction method worked better compared to the other methods in removing the terrain effects for snow covered areas. The importance of topographic normalization in mapping the effective snow covered area in snowmelt modeling is also discussed and the early findings of Satellite Application Facilities on Hydrology (H-SAF) project, which is financially supported by EUMETSAT, is presented. Turkey is a part of the H-SAF project, both in product generation (e. g. snow recognition, fractional snow cover and snow water equivalent) for mountainous regions for whole Europe, cal/val of satellite-derived snow products with ground observations (synoptic, automated weather stations and snow courses) and impact studies with hydrological modeling in the mountainous terrain of Europe.

Suggestions

Assessment of slope stability for a segment (km: 25+600-26+000) of Antalya-Korkuteli highway
Arıkan, Huriye Aslı; Topal, Tamer; Department of Geological Engineering (2010)
The cut slopes at a segment between Km 25+600 and 26+000 of the Antalya-Burdur Breakaway-Korkuteli State Road to be newly constructed have slope instability problems due to the existence of highly jointed limestone. The purpose of this study is to investigate the engineering geological properties of the units exposed at three cut slopes, to assess stability of the cut slopes, and to recommend remedial measures for the problematic sections. In this respect, both field and laboratory studies have been carried...
Assessment of rock slope stability by slope mass rating (SMR): A case study for the gas flare site in Assalouyeh, South of Iran
AZARAFZA, Mohammad; Akgün, Haluk; ASGHARI-KALJAHI, Ebrahim (2017-10-01)
Slope mass rating (SMR) is commonly used for the geomechanical classification of rock masses in an attempt to evaluate the stability of slopes. SMR is calculated from the RMR89-basic (basic rock mass rating) and from the characteristic features of discontinuities, and may be applied to slope stability analysis as well as to slope support recommendations.
Determination of tunnel support systems of Belkahve (İzmir) tunnel with empirical and numerical methods
Domaniç, Can Murat; Topal, Tamer; Department of Geological Engineering (2016)
In this study, determining the geological and geotechnical characteristics of the Belkhave tunnel with a length of 1650 m and width of 16 m along Manisa-İzmir Highway, selecting the appropriate support system and verifying with numerical modeling are aimed. Limestone and schist are the main lithologies along the Belkahve tunnel. RMR, Q and NATM classification systems are used to classify the rock mass. Appropriate support systems are determined by using these classification methods. In order to verify the d...
Assessment of discontinuous rock slope stability with block theory and numerical modeling: a case study for the South Pars Gas Complex, Assalouyeh, Iran
AZARAFZA, Mohammad; ASGHARI-KALJAHI, Ebrahim; Akgün, Haluk (Springer Science and Business Media LLC, 2017-06-01)
In this study, a geotechnical model has been used to analyze the stability of a discontinuous rock slope. The main idea behind block theory is that it disregards many different combinations of discontinuities and directly identifies and considers critical rock blocks known as "key blocks". The rock slope used as a case study herein is situated in the sixth phase of the gas flare site of the South Pars Gas Complex, Assalouyeh, Iran. In order to analyze the stability of discontinuous rock slopes, geotechnical...
Contribution of the satellite-data driven snow routine to a karst hydrological model
Çallı, Süleyman Özdemir; Çallı, Kübra Özdemir; Yılmaz, Mustafa Tuğrul; ÇELİK, MEHMET (2022-04-01)
Snow recharge is an important dominant hydrological process in the high altitude mountainous karstic aquifer systems. In general, widely used karst-dedicated hydrological models (e.g., KarstMod, Varkarst) do not include a snow routine in the model structure to avoid increasing the number of model parameters while representing the complex hydrological process. As a result, recharge process is not represented well, which questions the optimality of the results that can be obtained under available datasets. Th...
Citation Formats
S. Z. Akyürek, “Assessment of different topographic corrections in MODIS data for mapping effective snow covered areas in mountainous terrain,” 2008, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/39318.