Thermal constraints on energy balance, behaviour and spatial distribution of grizzly bears

2021 ◽  
Vol 35 (2) ◽  
pp. 398-410
Author(s):  
Savannah A. Rogers ◽  
Charles T. Robbins ◽  
Paul D. Mathewson ◽  
Anthony M. Carnahan ◽  
Frank T. Manen ◽  
...  
Keyword(s):  
Spatial Distribution ◽  
Energy Balance ◽  
Grizzly Bears ◽  
Thermal Constraints

scholarly journals Quantifying the evaporation amounts of 75 high-elevation large dimictic lakes on the Tibetan Plateau

2020 ◽  
Vol 6 (26) ◽  
pp. eaay8558 ◽  
Author(s):  
Binbin Wang ◽  
Yaoming Ma ◽  
Zhongbo Su ◽  
Yan Wang ◽  
Weiqiang Ma
Keyword(s):  
Spatial Distribution ◽  
Energy Balance ◽  
Tibetan Plateau ◽  
Satellite Data ◽  
High Elevation ◽  
The Tibetan Plateau ◽  
Large Variability ◽  
Plausible Hypothesis ◽  
Lake Evaporation ◽  
Hydrological Cycles

Lake evaporation can influence basin-wide hydrological cycles and is an important factor in loss of water resources in endorheic lakes of the Tibetan Plateau. Because of the scarcity of data, published lake evaporation values are inconsistent, and their spatial distribution has never been reported. Presenting a plausible hypothesis of energy balance during the ice-free seasons, we explored the multiyear (2003–2016) average ice phenology and evaporation amounts of 75 large dimictic lakes by using a combination of meteorological and satellite data. Evaporation amounts show large variability in spatial distribution, with a pattern of higher values in the south. Lakes with higher elevation, smaller area, and higher latitude are generally associated with a shorter ice-free season and lower evaporation. The total evaporated water amounts have values of approximately 29.4 ± 1.2 km3 year−1 for the 75 studied lakes and 51.7 ± 2.1 km3 year−1 for all plateau lakes included.

scholarly journals Mid-IR Imaging of Orion BN/KL: Modeling of Physical Conditions and Energy Balance

2015 ◽  
Vol 11 (S315) ◽  
Author(s):  
Daniel Gezari ◽  
Frank Varosi ◽  
Eli Dwek ◽  
William Danchi ◽  
Jonathan Tan ◽  
...  
Keyword(s):  
Spatial Distribution ◽  
Energy Balance ◽  
Infrared Imaging ◽  
Field Of View ◽  
Data Sets ◽  
Total Field ◽  
Mid Infrared ◽  
Interference Filters ◽  
Physical Conditions ◽  
Imaging Mode

We have modeled two mid-infrared imaging photometry data sets to determine the spatial distribution of physical conditions in the BN/KL infrared complex. We observed the BN/KL region using the 10-m Keck I telescope and the LWS in the direct imaging mode, over a 13” × 19” field (Figure 1, left). We also modeled images obtained with COMICS (Kataza et al. 2000) at the 8.2-m SUBARU telescope, over a total field of view is 31” × 41” (Figure 1, right), in a total of nine bands: 7.8, 8.8, 9.7, 10.5, 11.7, 12.4, 18.5, 20.8 and 24.8 μm with ~1 μm bandwidth interference filters.

scholarly journals Spatial distribution of debris thickness and melting from remote-sensing and meteorological data, at debris-covered Baltoro glacier, Karakoram, Pakistan

2008 ◽  
Vol 48 ◽  
pp. 49-57 ◽  
Author(s):  
C. Mihalcea ◽  
C. Mayer ◽  
G. Diolaiuti ◽  
C. D’Agata ◽  
C. Smiraglia ◽  
...  
Keyword(s):  
Remote Sensing ◽  
Spatial Distribution ◽  
Energy Balance ◽  
Meteorological Data ◽  
Thickness Distribution ◽  
Global Radiation ◽  
Model Performance ◽  
Thermal Characteristics ◽  
Lateral Moraine ◽  
Balance Study

AbstractA distributed surface energy-balance study was performed to determine sub-debris ablation across a large part of Baltoro glacier, a wide debris-covered glacier in the Karakoram range, Pakistan. The study area is ~124km2. The study aimed primarily at analyzing the influence of debris thickness on the melt distribution. The spatial distribution of the physical and thermal characteristics of the debris was calculated from remote-sensing (ASTER image) and field data. Meteorological data from an automatic weather station at Urdukas (4022ma.s.l.), located adjacent to Baltoro glacier on a lateral moraine, were used to calculate the spatial distribution of energy available for melting during the period 1–15 July 2004. The model performance was evaluated by comparisons with field measurements for the same period. The model is reliable in predicting ablation over wide debris-covered areas. It underestimates melt rates over highly crevassed areas and water ponds with a high variability of the debris thickness distribution in the vicinity, and over areas with very low debris thickness (<0.03 m). We also examined the spatial distribution of the energy-balance components (global radiation and surface temperature) over the study area. The results allow us to quantify, for the study period, a meltwater production of 0.058 km3.

scholarly journals Research on evaporation of Taiyuan basin area by using remote sensing

2005 ◽  
Vol 2 (1) ◽  
pp. 209-227 ◽  
Author(s):  
X. Jin ◽  
L. Wan ◽  
Z. Su
Keyword(s):  
Remote Sensing ◽  
Spatial Distribution ◽  
Energy Balance ◽  
Surface Energy ◽  
Land Surface ◽  
Surface Energy Balance ◽  
Remote Sensing Data ◽  
Sensing Data ◽  
Taiyuan Basin ◽  
Basin Area

Abstract. Taiyuan basin is enclosed by hills and mountains, located in the middle of Shanxi province, standing between longitudes 111°40'–113°00'E and latitude 37°00'–38&amp;deg00'N. With various types and wide distribution, the mineral resources are very abundant in this basin area. However, there is a great shortage of water resources. Due to continual fall of groundwater level caused by excessive extraction of ground water, some severe environmental problems are induced in this area, such as ground subsidence, etc. The goal of this paper is to estimate the spatial distribution of actual evaporation over the basin by using remote sensing data. The Surface Energy Balance System (SEBS) has been developed (Su, 2001, 2002). Using visible and infrared satellite remote sensing data, SEBS is based on land surface energy balance theory combined with the in-situ meteorological data or the product of atmospheric numerical model to estimate land surface turbulent flux and the relative evaporation at different scales. SEBS was served as the core methodology of this paper and was used for evaporation estimation. On the basis of hydro-geological data and NOAA satellite data, the SEBS was used in this paper for the estimation of actual evaporation of Taiyuan basin. The spatial distribution of the evaporative fraction and daily evaporation over the basin area was shown. On the other hand, the difference of land surface parameters and evaporation for various target types in the basin area was discussed.

scholarly journals O MODELO SEBAL PARA ESTUDOS DE CLIMA INTRAURBANO: APLICAÇÃO EM RECIFE, PERNAMBUCO, BRASIL - THE SEBAL MODEL FOR CLIMATE INTRA-URBAN STUDIES: APPLICATION IN RECIFE, PERNAMBUCO, BRAZIL

2017 ◽  
Vol 39 ◽  
pp. 247
Author(s):  
Elvis Bergue Mariz Moreira ◽  
Ranyére Silva Nóbrega ◽  
Bernardo Barbosa Da Silva ◽  
Eberson Pessoa Ribeiro
Keyword(s):  
Spatial Distribution ◽  
Energy Balance ◽  
Latent Heat ◽  
Urban Areas ◽  
Low Cost ◽  
Urban Climate ◽  
Remote Sensing Data ◽  
Heat Fluxes ◽  
Land Use Patterns ◽  
Landsat 5 Tm

O conhecimento dos componentes do balanço de energia em áreas urbanas é de grande importância para os estudos do clima urbano, principalmente quando estas são objeto de análise espacial. O objetivo deste estudo é adaptar o modelo SEBAL (comumente utilizado para fins agroclimatológicos) em um ambiente intraurbano, possibilitando análises de componentes microclimáticas com metodologia de baixo custo, através de dados de sensores remotos. A fim de alcançar este objetivo, seis imagens do satélite Landsat 5 TM, entre os anos de 1998 a 2011, foram processadas. Densidade dos fluxos de calor sensível e latente foram calculadas usando o algoritmo SEBAL. De acordo com os resultados, o elevado percentual de superfícies impermeáveis e a distribuição espacial reduzida de áreas verdes modificam as trocas entre os fluxos de radiação, proporcionando assim altos níveis de fluxos de energia disponíveis para o aumento da temperatura do ar. A este respeito, o setor oriental se destaca por seus valores de magnitude mais altas, entre 216 e 425 Wm-2. A área Sul produziu alguns valores em excesso de 426 Wm-2. O fluxo de calor latente (LE) apresentou diminuição da distribuição espacial; sendo concentrada em áreas protegidas designadas e corpos d'água com valores superiores a 431 Wm-2. Torna-se evidente que os padrões intensivos de uso da terra não coincidem com planejamento adequado e refletem sobre a qualidade de vida da população.ABSTRACTThe knowledge of the components of the energy balance in urban areas is of relevant to the studies of the urban climate, mainly when those are subject to spatial analysis. The objective of this study is to adapt the SEBAL - Surface Energy Balance Algorithm for Land model (commonly used to agroclimatic purposes) in a intra-urban environment, enabling analysis of microclimate components with low cost methodology through remote sensing data. In order to accomplish this goal, six satellite Landsat 5 TM images, between the sequential days of the years 1998 to 2011 were processed. Sensible and latent heat fluxes density were calculated using the SEBAL algorithm. According to the results, the high percentage of impervious surfaces and the reduced spatial distribution of green areas alter the exchanges among radiation fluxes, thus providing high levels of available energy fluxes for increasing air temperature. In this regard, the eastern sector stands out for its higher magnitude values, between 216 and 425 W m-². The South area yielded some values in excess of 426 W m-². Latent heat flux (LE) exhibited reduced spatial distribution; being concentrated in designated protected areas and water bodies with values higher than 431 W m-². It becomes evident that intensive land use patterns not matched by adequate planning reflect upon the quality of life of the population.

Spatial estimation of snow water equivalent by modeling of the melting of seasonal snow and glacier in Iceland

2021 ◽  
Author(s):  
Andri Gunnarsson ◽  
Sigurður M. Garðarsson ◽  
Tómas Jóhannesson ◽  
Finnur Pálsson
Keyword(s):  
Spatial Distribution ◽  
Energy Balance ◽  
Power System ◽  
Mass Balance ◽  
Snow Cover ◽  
Snow Water Equivalent ◽  
Seasonal Snow ◽  
Glacier Melt ◽  
Fractional Snow Cover ◽  
Snow Water

&lt;p&gt;Runoff from seasonal snow- and glacier melt is critical for hydropower production and reservoir storage in Iceland as the energy system is strongly dependent on summer inflow. The isolation and high natural climate variability can pose a risk to the energy security of the power system as drought conditions and low-flow periods are usually not foreseen in great advance. Forecasting the timing, spatial distribution and magnitude of seasonal melt is a challenge and influences the operational control of energy infrastructure and long-term resource planning. As hydropower generation provides over 72% of the total average energy produced in Iceland, accurate forecasting of seasonal melt is essential for the operation of the national power system.&lt;/p&gt;&lt;p&gt;In this study, we present results from a spatially-distributed energy-balance model combined with gap-filled satellite-based time series of fractional snow cover and surface albedo from MODIS. The model reconstructs seasonal snow and glacier melt for the Icelandic highlands providing insight into the spatio-temporal distribution of snow water equivalent over the study period. &amp;#160;The reconstruction method uses daily, satellite-derived estimates of fractional snow cover and albedo to scale the melt flux at every pixel. Modeled snow melt was integrated over time, reconstructing the maximum snowpack/glacier melt for each year. The model runs at a 500 m spatial resolution, with a daily timestep from 1 March to 30 September during 2000 to 2019 spanning the general seasonal snow and glacier melt period.&lt;/p&gt;&lt;p&gt;Energy-balance components were validated with in-situ observations from the Icelandic highlands and a network of stations operated annually at various Icelandic glaciers. Ground-based measurements of snow water equivalent (snow pits, surface mass balance) were used to validate the model performance as well as discharge observations. Simulations indicate a good performance compared with summer glacier mass balance records from Vatnaj&amp;#246;kull, Hofsj&amp;#246;kull, Langj&amp;#246;kull and M&amp;#253;rdalsj&amp;#246;kull. Sparse and discontinuous measurements of seasonal snow water equivalent from snow pillows or transects from snow courses were available from a few location, providing limited capabilities for direct validation for seasonal snow. Discharge observations in highland catchments indicate acceptable performance.&lt;/p&gt;&lt;p&gt;The results allow for quantification of the spatial distribution of snow water equivalent, relationships to elevation and other topographical parameters as well as between basins and years. Discrimination between seasonal snow and glacier melt on a catchment scale is valuable to analyze the annual variability in these two critical hydrological water sources and how they are related.&lt;/p&gt;

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