spatial and temporal resolution

Top PDF spatial and temporal resolution:

Conference paper

Conference paper

identify the pixels with distinct heat flux properties which in- turn decides the performance of the model. Conversely, the satellites with high spatial resolution have low repeat cycles. Spatial and Temporal Adaptive Reflectance Fusion Model (STARFM) and Spatial Temporal Adaptive Algorithm for Mapping Reflectance Change (STAARCH) simulated reflectance data at fine spatial and temporal resolution by combining the spatial information from fine resolution imagery integrated with the temporal information acquired from coarse resolution imagery (Gao et al., 2006; Hilker et al., 2009). Moreover, assumption of linearity in the rate of change of reflectance across a period cannot be valid in the case of pixels representing agriculture, which has a unique non linear crop phonological cycle. Hence, methods that integrate change in crop phenology within the disaggregation scheme will be effective in capturing the temporal variability across a season in spatial disaggregation.
Baca lebih lanjut

5 Baca lebih lajut

isprsarchives XL 1 W3 165 2013

isprsarchives XL 1 W3 165 2013

Snow cover analyses in mountainous regions are important for various purposes such as snow mapping, climate studies, and predicting discharg or snowmelt runoff forecasting. An early warning of snow-caused disasters will be a decisive as well as contributory factor in policymakers' decisions regarding the diminution of the potential damages caused by snow. Snow ground measurements implemented at climate stations facilitate the provision of authoritative information about snow depth in a specific region which is considered as important ground control points for validation of snow cover extent (SCE) determined by remote sensing tools. According to extreme environmental conditions in different parts of an area, in situ measurements are limited and therefore monitoring the spatial variation of snow cover area (SCA) poses a multitude of difficulties. Moreover, airborne measurements only have the capability to obtain the information of snow in local scales and brief duration. Satellite-based remote sensing has provided a useful tool for spatial and temporal monitoring of variation and distribution of SCE in regional and global scales. Satellite data in the visible and the infra-red spectrum as well as in the passive microwaves represent an alternative source of information on snow cover. Snow cover products provided by microwave sensors such as Scanning Multichannel Microwave Radiometer (SMMR), Special Sensor Microwave/Imager (SSM/I) and Advanced Microwave Scanning Radiometer–EOS (AMSR-E) are used to monitor SCA in global scale due to their coarse spatial resolution. The images of LANDSAT optical sensor has a higher spatial resolution comparing to microwave data, but its low temporal resolution (16 day) circumscribes the ability of this satellite in monitoring SCE. The Moderate Resolution Imaging Spectroradiometer (MODIS), carried aboard the Terra spacecraft launched in 1999 and Aqua satellite launched in 2002, provides the only global snow cover products available at sufficient spatial and temporal resolution to monitor snow extent. The freely MODIS images, with 500 m spatial and daily temporal resolution, available from 2000 to present,
Baca lebih lanjut

4 Baca lebih lajut

isprs annals IV 4 W2 183 2017

isprs annals IV 4 W2 183 2017

downloaded from https://giovanni.sci.gsfc.nasa.gov/giovanni/. And the TRMM 3B42 data has a 0.25degree spatial resolution and 3 hourly temporal resolution, covering the latitudinal band about 50S-50N for the period 1997 to present. (Kummerow, Barnes, Kozu, Shiue, & Simpson, 1998). The TRMM/TMPA 3B42 rainfall estimates are produced in four stages: (1) the microwave precipitation estimates are calibrated and combined, (2) infrared precipitation estimates are created using the calibrated microwave precipitation, (3) the microwave and IR estimates are combined, and (4) rescaling to monthly data is applied. Each precipitation field is best interpreted as the precipitation rate effective at the nominal observation time (Huffman, et al., 2007). The sources of its passive Microwave satellite precipitation estimates include: TRMM Microwave Imager (TMI), Special Sensor Microwave Imager (SSMI), Special Sensor Microwave Imager/Sounder (SSMIS) (3B42V7 only), Advanced Microwave Scanning Radiometer-EOS (AMSR-E), Advanced Microwave Sounding Unit-B (AMSU-B), and Microwave Humidity Sounder (MHS) (Chen, et al., 2013). And the IR data are from National Climatic Data Center (NCDC) and Climate Prediction Center (CPC), which are calibrated by the Microwave data according to the algorithm. It also incorporates the latest version 4 of Global Precipitation Climatology Centre (GPCC) full-gauge analysis from 1998 to 2010 and the GPCC monitoring gauge analysis since 2010 (Moazami, et al., 2013).
Baca lebih lanjut

9 Baca lebih lajut

Conference paper

Conference paper

Interest in data fusion, for remote-sensing applications, continues to grow due to the increasing importance of obtaining data in high resolution both spatially and temporally. Applications that will benefit from data fusion include ecosystem disturbance and recovery assessment, ecological forecasting, and others. This paper introduces a novel spatiotemporal fusion approach, the wavelet-based Spatiotemporal Adaptive Data Fusion Model (WSAD-FM). This new technique is motivated by the popular STARFM tool, which utilizes lower-resolution MODIS imagery to supplement Landsat scenes using a linear model. The novelty of WSAD-FM is two- fold. First, unlike STARFM, this technique does not predict an entire new image in one linear step, but instead decomposes input images into separate “ approximation ” and “ detail ” parts. The different portions are fed into a prediction model that limits the effects of linear interpolation among images. Low-spatial-frequency components are predicted by a weighted mixture of MODIS images and low-spatial-frequency components of Landsat images that are neighbors in the temporal domain. Meanwhile, high-spatial- frequency components are predicted by a weighted average of high-spatial-frequency components of Landsat images alone. The second novelty is that the method has demonstrated good performance using only one input Landsat image and a pair of MODIS images. The technique has been tested using several Landsat and MODIS images for a study area from Central North Carolina (WRS-2 path/row 16/35 in Landsat and H/V11/5 in MODIS), acquired in 2001. NDVI images that were calculated from the study area were used as input to the algorithm. The technique was tested experimentally by predicting existing Landsat images, and we obtained R 2 values in the range 0.70 to 0.92 for estimated Landsat images in the red band, and 0.62 to 0.89 for estimated NDVI images.
Baca lebih lanjut

8 Baca lebih lajut

Assessment of temporal and spatial changes of future climate in the Jhelum river basin, Pakistan and India

Assessment of temporal and spatial changes of future climate in the Jhelum river basin, Pakistan and India

In the last few decades, Global Climate Models (GCMs) — the most advanced and numerical-based coupled models representing the global climate system—have been used to examine future changes in climate variables such as temperature, precipitation, and evaporation (Fowler et al., 2007). However, their outputs are temporally and spatially very coarse (Gebremeskel et al., 2005), which makes them useful only at continental and global levels. Their application at local/regional levels, such as at the basin and sub-basin scales, to assess the impacts of climate change on the environment and hydrological cycle, is problematic due to a clear resolution mismatch (Hay et al., 2000; Wilby et al., 2000). That is, GCMs cannot give a realistic presentation of local or regional scales due to parameterization limitations (Benestad et al., 2008). The local and regional scales are de fi ned as 0 – 50 km and 50 50 km 2 , respectively (Xu, 1999)
Baca lebih lanjut

16 Baca lebih lajut

isprsarchives XL 7 W3 525 2015

isprsarchives XL 7 W3 525 2015

Utilization of remote sensing satellite data has been carried out extensively to support various sectors, such as agriculture, forestry, water resources, marine fisheries and disaster mitigation. Nowadays, optical satellite sensor is still the most widely used sensor, because it can record the satellite data with high spatial, high temporal and high spectral resolution. By those capabilities, optical satellite data can give the detail information of the objects (i.e. shape, colour) which are closely similar to the condition of real objects on the earth's surface. The main problems of optical data are the presence of cloud cover (electromagnetic waves in the visible to infrared range are reflected by cloud), and also the dependency on sunlight as a light source. These problems caused a lot of data acquired by optical sensor could not be used due to the high cloud cover. Synthetic Aperture Radar (SAR) is one of the most promising satellite sensors for monitoring the earth surface at a regional to global scale. SAR has many useful characteristics for supporting various applications, such as cloud-free, day or night observation capability, highly spatial resolution produced by the synthetic aperture technique, and also polarimetric and interferometric information (JAXA, 2012). In particular, cloud- free observation by SAR is a great advantage for monitoring in humid tropical regions such as Indonesia. Regarding to that reason, it is very important to explore the potentiality of SAR capability and utilize the SAR data to support various applications needed in Indonesia.
Baca lebih lanjut

5 Baca lebih lajut

Study Spatial and Temporal of Coral Reef State and Reef Fish Community after Tsunami In Weh and Aceh Islands Waters

Study Spatial and Temporal of Coral Reef State and Reef Fish Community after Tsunami In Weh and Aceh Islands Waters

The Tsunami in Aceh had caused to the damage of the Aceh nese reefs ecosystem. However, the ability to recover is naturally found in the coral reef. The purpose of the research are to determine percentages of hard coral cover and coral recruitment in Weh and Aceh Islands. The research was conducted in 2006, 2008, 2009, and 2011. The research was done in Aceh islands, utilization areas, marine natural tourist park (TWAL) and regional marine conservation areas (KKLD). Point Intercept Transect (PIT) and square transect Methods were applied in the research. The research showed that the percentages of hard coral cover in 2011 in Aceh island and utilization areas are 49,38% and 34,16 %, respectively. On the other hand, in marine natural tourist park (TWAL) and regional marine conservation areas (KKLD) are 32,66% and 41,27 % respectively. The percentages of coral cover had increased from 2006, 2008 to 2009. Meanwhile in the percentages of coral cover marine natural tourist park (TWAL) and regional marine conservation areas (KKLD) decreased in 2011. The highest recruitment occurred in 2008 in all survey areas and decreased in 2009. Thus, this study concluded that there existed a recovery of coral reef ecosystem with an increase in the percentage of hard coral cover and coral recruitment from 2006 to 2011. The highest abundances of reef fish in 2011 were found in marine natural tourist park (TWAL) with total amount and biomasses of 15.559 individual/ha and 1.574,43 kg/ha, respectively.
Baca lebih lanjut

270 Baca lebih lajut

AN ANALYSIS OF DEIXIS USED BY HELEN AS THE MAIN CHARACTER IN GEORGE SULLIVAN’S NOVEL “HELEN KELLER”

AN ANALYSIS OF DEIXIS USED BY HELEN AS THE MAIN CHARACTER IN GEORGE SULLIVAN’S NOVEL “HELEN KELLER”

This study used qualitative research design because it investigates the utterances of the deixis used by Helen as the main character in George Sul livan’s novel “Helen Keller” by using human as the instrument. In collecting the data, In collecting the data, the writer read to understandd the novel, selected the data dealing with the problems which become the focus of the study, namely deixis, rewrote all of the data which have been selected based on the original quotation in the novel “ Helen Keller ”. Then, the writer analyzed by identifying the data which were categorized as deixis, analyzing the data based on person, spatial, and temporal deixis, and describing and developing the results of analysis into good sentences by presenting the proofs.
Baca lebih lanjut

13 Baca lebih lajut

View of Perkembangan Temporal-Spatial Penyakit Layu Stewart (Pantoea stewartii subsp. stewartii) Pada Tanaman Jagung Temporal-Spatial Development of Stewart Wilt (Pantoea stewartii subsp. stewartii) on Corn

View of Perkembangan Temporal-Spatial Penyakit Layu Stewart (Pantoea stewartii subsp. stewartii) Pada Tanaman Jagung Temporal-Spatial Development of Stewart Wilt (Pantoea stewartii subsp. stewartii) on Corn

Severitas penyakit pada periode Juli-September 2015 lebih tinggi daripada severitas penyakit pada periode tanam Maret-Mei 2015, jika dikaitkan dengan kandungan pospor dan nitrogen yang juga lebih tinggi pada periode tanam Juli- September 2015 daripada periode tanam Maret-Mei 2015.Kondisi tersebut sesuai dengan hasil penelitian yang menyatakan bahwa penyakit layu Stewart lebih cocok pada daerah dengan kandungan nitrogen dan pospor tinggi (Plant and Pest Diagnostic Laboratory Purdue University, 2012).Demikian juga dengan hasil penelitian Aydogdu (2011) tentang pengaruh nitrogen dan pupuk organik terhadap severitas penyakit corn smut (Ustilago maydis(DC) Corda) yang membuktikan bahwa severitas penyakit mengalami peningkatan akibat pemberian nitrogen dan pupuk organik, jadi jumlah nitrogen dan pupuk oganik merupakan faktor penting yang mempengaruhi severitas penyakit.
Baca lebih lanjut

15 Baca lebih lajut

The Spatial-Temporal Anomaly Detection Algorithm in Wireless Sensor Networks

The Spatial-Temporal Anomaly Detection Algorithm in Wireless Sensor Networks

The traffic forecast model [8] uses the correlation coefficient of predicted traffic sequences and the actual flow sequence for anomaly detection. The spatialtemporal correlation characteristics of the sensor data were considered in [9], which used time and spatial correlations to generate outliers. The local outliers are converged to sink for the global outliers. This method is applied only to detect abnormal points, but sometimes, abnormal sequence detection helps to reveal abnormal events that occur. Thus, the time series of anomaly detection was more valuable in [10], which proposed to rapidly compare the similarities of two time series based on the Chebyshev coefficient and found an abnormal time sequence. The literature focused on outlier detection and a single time series of anomaly detection in the sensor data. The spatialtemporal characteristics of the sensor when the abnormal event occurred was overlooked [11].
Baca lebih lanjut

10 Baca lebih lajut

Directory UMM :Data Elmu:jurnal:A:Agricultural & Forest Meterology:Vol105.Issue1.Nov2000:

Directory UMM :Data Elmu:jurnal:A:Agricultural & Forest Meterology:Vol105.Issue1.Nov2000:

imately 50%. This unexpected discrepancy on this date could be due to several factors. One was the het- erogeneous nature of the study areas. Since ground sampling was made within several 2 × 2 m 2 blocks, the averaged values may not represent what a sen- sor would ‘see’ with a footprint of 30 × 30 m 2 area. The estimated GLAI, agreed reasonably well with in situ measurements. It should be pointed out that there were uncertainties associated with ground GLAI measurements. The uncertainty in the in situ GLAI measurements could result from spatial variation of the vegetation density, random errors of the equip- ment used, and measurement condition variations when using LAI-2000 instrument, resulting in dis- crepancies between in situ measurements and remote estimates.
Baca lebih lanjut

14 Baca lebih lajut

Study Spatial and Temporal of Coral Reef State and Reef Fish Community after Tsunami In Weh and Aceh Islands Waters

Study Spatial and Temporal of Coral Reef State and Reef Fish Community after Tsunami In Weh and Aceh Islands Waters

The Tsunami in Aceh had caused to the damage of the Aceh nese reefs ecosystem. However, the ability to recover is naturally found in the coral reef. The purpose of the research are to determine percentages of hard coral cover and coral recruitment in Weh and Aceh Islands. The research was conducted in 2006, 2008, 2009, and 2011. The research was done in Aceh islands, utilization areas, marine natural tourist park (TWAL) and regional marine conservation areas (KKLD). Point Intercept Transect (PIT) and square transect Methods were applied in the research. The research showed that the percentages of hard coral cover in 2011 in Aceh island and utilization areas are 49,38% and 34,16 %, respectively. On the other hand, in marine natural tourist park (TWAL) and regional marine conservation areas (KKLD) are 32,66% and 41,27 % respectively. The percentages of coral cover had increased from 2006, 2008 to 2009. Meanwhile in the percentages of coral cover marine natural tourist park (TWAL) and regional marine conservation areas (KKLD) decreased in 2011. The highest recruitment occurred in 2008 in all survey areas and decreased in 2009. Thus, this study concluded that there existed a recovery of coral reef ecosystem with an increase in the percentage of hard coral cover and coral recruitment from 2006 to 2011. The highest abundances of reef fish in 2011 were found in marine natural tourist park (TWAL) with total amount and biomasses of 15.559 individual/ha and 1.574,43 kg/ha, respectively.
Baca lebih lanjut

144 Baca lebih lajut

SPATIAL AND TEMPORAL DISTRIBUTION OF NATURAL ENEMIES VISITING REFUGIA IN A PADDY FIELD AREA IN MALANG

SPATIAL AND TEMPORAL DISTRIBUTION OF NATURAL ENEMIES VISITING REFUGIA IN A PADDY FIELD AREA IN MALANG

Human effort to control agricultural pests has been carried out intensively the damage of crops due to pests remain a major problem in plant cultivation. In a stable ecosystem pest problems will not occur because all components of the ecosystem in a state of balance. However, human activities in seeking agricultural lands, indirectly created an unnatural agricultural ecosystems (Kerr, 2009). Use of pesticides in controlling pest proven to have side effects such as target pests becoming resistant to pesticides, resurjensi pests, death of non target animal including natural enemies, the emergence of secondary pest, pesticide residues in crop, environmental contamination of soil, water and air, and impact on health (Agne et al. in Bahagiawati 2001). Eko (2008) stated that the residues of herbicides can alter several soil properties (soil degradation).
Baca lebih lanjut

8 Baca lebih lajut

Spatial and Temporal Analysis of Avian Influenza on Poultry Sector IV in Daerah Istimewa Yogyakarta Province

Spatial and Temporal Analysis of Avian Influenza on Poultry Sector IV in Daerah Istimewa Yogyakarta Province

The objectives of this research are to located the center on AI cases, spatial correlation and AI cases pattern identification, identifying the relationship between poultry population and the number of AI cases, locate areas that become hotspot and figure out AI cases temporal pattern. Data used in this research is a secondary data from Participatory Disease Surveillance and Response (PDSR) and Dinas Peternakan dan Kesehatan Hewan Provinsi DIY for number of AI cases, GPS coordinate and poultry population of each sub-district in DIY province in 2009-2012. Mean spatial, moran scatterplot, Chi-Square test, and ARIMA are used for data analysis. Result from this research is expected to provide information regarding AI disease to the central government, regional government, and public society as an advice for deciding the prevention policy and AI cases treatment in DIY province.
Baca lebih lanjut

62 Baca lebih lajut

MEMBANGUN PERADABAN YANG LEBIH ADIL

MEMBANGUN PERADABAN YANG LEBIH ADIL

Dalam kerangka itu Sen lebih pragmatis dan struktural. Dunia memerlukan pembaharuan institusional untuk memungkinkan terjadinya perubahan yang diperlukan supaya globalisasi itu menjadi pengaturan yang lebih adil. Dia antara lain menuntut dibukanya pasar negara-negara maju 30 untuk produsen negara-negara sedang berkembang serta humanisasi hak paten atas obat-obatan yang diperlukan untuk memerangi berbagai penyakit massal di dunia. Artinya, harus ada perubahan struktur global yang lebih emansipatif. John Rawls (1921-2002) malahan sudah sempat mendahului dengan rumus yang lebih praktis lagi: “The Law of Peoples (we) would adopt is the law that we you and I, here and now would accept as fair in specifying the basic terms of cooperation among people”. 31 Sulit untuk tidak membayangkan, bahwa basic terms itu ujung-ujungnya harus merupakan emansipasi dalam kesempatan untuk hidup lebih layak. Padahal itulah yang justru acapkali tidak direlakan oleh negara-negara dengan ekonomi dan industri yang sudah kuat. Ternyata merekalah yang lebih memerlukan proteksi ketimbang masyarakat-masyarakat yang kurang maju atau malahan tidak maju-maju, karena bagi orang miskin they have nothing to lose.
Baca lebih lanjut

17 Baca lebih lajut

Directory UMM :Data Elmu:jurnal:A:Agricultural Water Management:Vol43.Issue2.Mar2000:

Directory UMM :Data Elmu:jurnal:A:Agricultural Water Management:Vol43.Issue2.Mar2000:

The Intergovernmental Panel on Climate Change (IPCC) reported that `the balance of evidence suggests there is a discernible human influence on the global climate' (Department of the Environment, 1996). Indeed the spate of recent droughts experienced in UK are consistent with a changing climate. However, the likely impacts on UK irrigation are still far from clear. Recent estimates suggest higher temperatures with only marginally more summer rainfall in the main UK irrigation areas (Department of the Environment, 1996). Others show a marginal decrease in summer rainfall, further increasing potential soil moisture deficits (BHS, 1998). Extrapolating from recent Institute of Hydrology predictions and past quantitative relationships between climate variation and summer rainfall, Herrington (1996) estimated an additional 27.5% demand above current trends in EA Anglian Region by the year 2021. However, as he cautions, using relationships based on past variation to estimate the effects of change is likely to give an underestimate. Once the likely effects of climate change are more widely accepted, farmers can be expected to want to increase system capacity and irrigate more of their crops.
Baca lebih lanjut

16 Baca lebih lajut

isprs archives XLII 1 W1 283 2017

isprs archives XLII 1 W1 283 2017

column correction fails to eliminate the effect of water column attenuation on bottom reflectances. In contrast, applying Lyzenga’s algorithm on the denoised depth -invariant index (Fig. 3C) yields a seemingly more realistic representation of the bottom. The SVM-derived classification results comprise submerged habitat distribution maps of our survey site in the Thermaikos Gulf (Fig. 2D, 3D). Accuracy assessment (Table 3, 4) of the classifications of the resulting ‘noisy’ and denoised depth-invariant indices following application of UBD and empirical water column correction reflects the visual inspections. The denoised depth-invariant index of blue and green Planet reflectances improves overall accuracy and Kappa value from 53.2% and 0.26 to 68.1% and 0.5, respectively. Denoising aids detection of Posidonia oceanica seagrass species by increasing its producer and user accuracy by 31.7% and 10.4%, correspondingly, with a respective increase in its Kappa value from 0.3 to 0.48. On the other hand, both classified depth-invariant indices, before and after denoising, fail to detect Cymodocea nodosa seagrass species. Moreover, the error matrix indicates that P. oceanica seagrass class is mainly confused with sand class. Generally, denoising unveils fine, smaller patches of sand within the homogeneous P. oceanica meadows, an essential feature of the high spatial resolution Planet imagery towards finer scale seagrass detection. Both classification results lack clear delineation of the seaward limit of P. oceanica seagrass.
Baca lebih lanjut

5 Baca lebih lajut

Conference paper

Conference paper

Preservation of the spectral characteristics in multispectral images is important in the development of pansharpening methods because it affects the accuracy of subsequent applications, such as visual interpretation, land cover classification, and change detection. The combinations of the spectral properties (observation wavelength and width of spectral bands) of multispectral and panchromatic images affect both the spatial and spectral quality of pansharpened images. Therefore, the clarification of the relations between spectral bands and quality of pansharpened image is important for improving our understanding of pansharpening methods, and for developing better schemes for image fusion. This study investigated the influence of the spectral waveband of panchromatic images on the image quality of multispectral (MS) images using simulated images produced from hyperspectral data. Panchromatic images with different spectral band position and multispectral images with degraded spatial resolution were generated from airborne visible/infrared imaging spectrometer (AVIRIS) images and pansharpened using seven methods: additive wavelet intensity, additive wavelet principal component, generalized Laplacian pyramid with spectral distortion minimization, generalized intensity-hue- saturation (GIHS) transform, GIHS adaptive, Gram–Schmidt spectral sharpening, and block-based synthetic variable ratio. The pansharpened near-infrared band was visually and statistically compared with the non-degraded image. Wide variation in quality was identified visually within and between methods depending on the spectral wavelengths of the panchromatic images. Quantitative evaluations using three frequently used indices, the correlation coefficient, erreur relative globale adimensionnelle de synthèse (ERGAS), and the Q index, showed the individual behaviors of the pansharpening methods in terms of the spectral similarity in panchromatic and near-infrared, though all methods had similar qualities in the case with the lowest similarity. These findings are discussed in terms of the fundamentals and structures of the methods.
Baca lebih lanjut

6 Baca lebih lajut

Directory UMM :Data Elmu:jurnal:A:Agricultural & Forest Meterology:Vol105.Issue4.Dec2000:

Directory UMM :Data Elmu:jurnal:A:Agricultural & Forest Meterology:Vol105.Issue4.Dec2000:

Grassland functioning has been heavily investi- gated during the SALSA program. Two vegetation growth models have been developed (or adapted) and validated using data collected over grassland sites in the San Pedro river basin (Nouvellon et al., 2000a; Cayrol et al., 2000a). The descriptions of the basic vegetation processes (carbon balance, photosynthe- sis, respiration, and senescence) in both models are not fundamentally different, but their parameteriza- tions for energy and water exchanges are distinct, both in concept and complexity. The model devel- oped by Nouvellon et al. (2000a) describes the flux of water and energy using a simple approach which functions with a daily time step, while that of Cayrol et al. describes these same processes using a detailed two-layer model over 20 min time steps. Both models have been validated using multi-year data sets (al- though for different sites), and they both show very good agreement between observed and simulated above-ground biomass, leaf area index, and the soil water content for different layers. The question that arises here is what is the level of complexity and at what time step the exchanges of water and energy need to be parameterized in a model for vegetation functioning in order to capture the seasonal and the interannual dynamics of the grassland. Apparently, a simple model with a daily time step might be suffi- cient. However, more analyses are required before a firm answer to this question can be provided. First, both models need to be run over the same site. Sec- ond, the advantage offered by the Cayrol et al. model, which allows the assimilation of instantaneous esti- mates of surface temperature and surface soil moisture using remote-sensing, needs to be weighed against the increase of the number of additional parameters required. Both of the above issues will be addressed within the SALSA program in the near future.
Baca lebih lanjut

13 Baca lebih lajut

isprs archives XLII 2 W7 919 2017

isprs archives XLII 2 W7 919 2017

Remote sensing techniques have great potential in providing accurate and timely information in urban areas. Estimation of impervious surfaces has increasingly roused widely interests of researchers in monitoring urban development and determining the overall environmental health of a watershed. However, studies on the impervious surface using multi-spectral imageries is insufficient and inaccurate due to the complexity of urban infrastructures base on the need to further recognize these impervious surface materials in a finer scale. Hyperspectral imageries have been proved to be sensitive to subtle spectral differences thus capable to exquisitely discriminate these similar materials while limited to the low spatial resolution. Coupled nonnegative matrix factorization (CNMF) un- mixing method is one of the most physically straightforward and easily complemented hyperspectral pan-sharpening methods that could produce fused data with both high spectral and spatial resolution. This paper aimed to exploit the latent capacity and tentative validation of CNMF on the killer application of mapping urban impervious surfaces in complexed metropolitan environments like Hong Kong. Experiments showed that the fusion of high spectral and spatial resolution image could provide more accurate and comprehensive information on urban impervious surface estimation.
Baca lebih lanjut

5 Baca lebih lajut

Show all 10000 documents...