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International audience; Evapotranspiration (ET) is a key process in land surface–atmosphere studies. It mainly depends on water availability and incoming solar radiation and then reflects the interactions between surface water processes and climate. In this paper, a methodology for retrieving ET from low spatial resolution remote sensing data is presented. It is based on the evaporative fraction concept, and it has been applied to Advanced Very High Resolution Radiometer (AHVRR) data acquired over the Iberian Peninsula. The methodology does not require other data than the data provided by the satellite and may be applied to areas with almost spatially constant atmospheric conditions and which include wet and dry sub-areas. The comparison with high resolution ET estimation shows a root mean square error (RMSE) of 1.4 mm d− 1 which is in agreement with the sensitivity analysis of the method. Finally, the methodology has been applied to temporal NOAA–AVHRR images acquired from 1997 to 2002 in order to analyze the seasonal evolution of the daily ET. The temporal study of the ET values realized in this paper shows that the highest ET values are associated with the higher development crops, while the lowest values are related with lower development or null crop. As a conclusion, it is shown that the ET values obtained with the proposed model evolve according to the variations presented in parameters such as surface temperature or vegetation index

Oceans cover about 70% of the earth’s surface. They are the largest source of the atmospheric water vapour and act as enormous heat reservoirs. Thus in order to predict the future weather and climate it is of great importance to understand the processes governing the exchange of water vapour and heat between the ocean and atmosphere. This exchange is to a large extent mediated by turbulent eddies. Current numerical climate and weather forecast models are unable to resolve the turbulence, which means that the turbulent exchange needs to be simplified by using parameterizations. Tower based measurements at the Östergarnsholm Island in the Baltic Sea have been used to study the air-sea turbulent exchange of latent and sensible heat and the heat flux parameterizations. Although the measurements are made at an island, data obtained at this site is shown to represent open ocean conditions during most situations for winds coming from the east-south sector. It is found that during conditions with small air-sea temperature differences and wind speeds above 10 m s-1, the structure of the turbulence is re-organized. Drier and colder air from aloft is transported to the surface by detached eddies, which considerably enhance the turbulent heat fluxes. The fluxes where observed to be much larger than predicted by current state-of-the-art parameterizations. The turbulence regime during these conditions is termed the Unstable Very Close to Neutral Regime, the UVCN-regime. The global increase of the latent and sensible heat fluxes due to the UVCN-regime is calculated to 2.4 W m-2 and 0.8 W m-2 respectively. This is comparable to the current increase of the radiative forcing due to anthropogenic emissions of greenhouse gases, reported in Intergovernmental Panel on Climate Change fourth assessment report (IPCC AR4). Thus the UVCN-effect could have a significant influence when predicting the future weather and climate.

The definitive version is available at: http://www.sciencedirect.com/science/journal/01681923, The performance of surface renewal (SR) analysis for estimating sensible (H) and latent (λE) heat fluxes has been analysed over a sprinkler irrigated rice. Similarity principles were not fully met during the experiment and the (H + λE) measured values with the eddy covariance did not close the surface energy balance. H and λE estimates using SR analysis were reliable and provided a reasonable energy-balance closure. The Bowen ratio was also estimated using SR analysis. Good estimates were obtained though mainly under unstable atmospheric conditions., This study was supported by projects REN2001/CLI1630, TRANSCLA and AGL2000-1775-C03-02.

The exchange of water, carbon, and energy between grasslands and the atmosphere is an important biogeochemical pathway affecting ecosystem productivity and sustainability. The eddy covariance (EC) technique directly measures this mass and energy exchange. However, questions remain regarding the accuracy of EC-derived H[subscript]2O and CO[subscript]2 fluxes in landscapes with irregular topography and variable vegetation. These concerns stem from the "energy balance (EB) closure problem" (i.e., measured energy in does not equal measured energy out). My main objectives were to examine EB closure at two topographical positions within an annually burned tallgrass prairie watershed and to examine the effect of landscape position and woody encroachment on carbon and water exchanges. In tallgrass prairie, 14 km south of Manhattan, KS, USA, EC towers were deployed at three sites in 2007 and 2008. One upland and lowland tower were within an annually burned watershed dominated by C[subscript]4 grasses. Another lowland tower was deployed in a separate quadrennial-burned watershed where significant woody vegetation occupied the tower's sampling area. All towers measured EB components (net radiation, R[subscript]n; soil heat flux, G; sensible heat flux, H; and latent heat flux, [lambda]E). In the annually burned watershed, landscape position had little effect on G, H, and R[subscript]n with differences [less than] 2% between sites. However lowland [lambda]E was 8% higher, owing to larger plant biomass/leaf area and greater soil moisture. Energy balance closure (i.e., [[lambda]E + H] / [R[subscript]n - G]) was 0.87 and 0.90 at the upland and lowland sites, respectively. A nearby large-aperture scintillometer provided good validation of EC-derived H in 2007. Data suggested that underestimates of [lambda]E may have accounted for the closure problem; sample calculations showed that increasing [lambda]E by 17% would have resulted in near prefect closure. Data from this study suggests that EB closure does not strongly correlate with topographical position; however these data raise questions regarding accuracy of the [lambda]E term. Mass exchange analysis shows that the prairie carbon cycle is highly dependent on burning. The lowland and upland annually burned sites saw carbon gains of 281 to 444 g C m[superscript]-[superscript]2 yr[superscript]-[superscript]1 before burning with the shrub lowland showing the least (e.g. 159 and 172 g C m[superscript]-[superscript]2 yr[superscript]-[superscript]1). After the prescribed burn, the upland and lowland sites remained slight carbon sinks (68 to 191 g C m[superscript]-[superscript]2 yr[superscript]-[superscript]1), whereas the unburned shrub site was a carbon sink in 2007 (159 g C m[superscript]-[superscript]2 yr[superscript]-[superscript]1, because no carbon loss was incurred via burning) and a large carbon source in 2008 when it was burned the following year (336 g C m[superscript]-[superscript]2 yr[superscript]-[superscript]1 loss). Evapotranspiration (ET) was highest at the shrub lowland where greater soil moisture and abundance of deep-rooted C[subscript]3 shrub vegetation allowed greater uptake and loss of water

Accurate information on the distribution of sensible and latent heat fluxes as well as soil moisture is critical for evaluation of background characteristics. Since these fluxes are subject to rapid changes in time and space, it is nearly impossible to determine their spatial and temporal distributions over large areas from ground measurements alone. Therefore, prediction from remote sensing images is very attractive as it enables extensive area coverage and a high repetition rate. In this study, the Surface Energy Balance Algorithm for Land as implemented at New Mexico Tech (SEBALNM) is used to estimate sensible and latent heat fluxes in the White Volta Basin of Ghana, West Africa. The objectives are (i) to demonstrate a SEBALNM application in a part of the world were ground measurements are very scarce and (ii) to compare evapotranspiration (ET) maps obtained from Landsat and MODIS imagery, respectively. The results of this study demonstrate that SEBALNM can be applied for mapping sensible and latent heat fluxes as well as soil moisture over areas where few or no ground measurements are available using common satellite products (Landsat and MODIS).

Accurate information on the distribution of sensible and latent heat fluxes as well as soil moisture is critical for evaluation of background characteristics. Since these fluxes are subject to rapid changes in time and space, it is nearly impossible to determine their spatial and temporal distributions over large areas from ground measurements alone. Therefore, prediction from remote sensing images is very attractive as it enables extensive area coverage and a high repetition rate. In this study, the Surface Energy Balance Algorithm for Land as implemented at New Mexico Tech (SEBALNM) is used to estimate sensible and latent heat fluxes in the White Volta Basin of Ghana, West Africa. The objectives are (i) to demonstrate a SEBALNM application in a part of the world were ground measurements are very scarce and (ii) to compare evapotranspiration (ET) maps obtained from Landsat and MODIS imagery, respectively. The results of this study demonstrate that SEBALNM can be applied for mapping sensible and latent heat fluxes as well as soil moisture over areas where few or no ground measurements are available using common satellite products (Landsat and MODIS).

We present new analytical results relating to the growth and evolution of sea ice. It is noteworthy that thin sea ice plays a central role in the surface heat and mass balance of the Arctic Ocean. In order to describe these balances, we analyze highly resolved temperature data taken through the air/sea/ice interface during the transition from an ice-free to an ice-covered Arctic Ocean surface. Our detailed analysis of the field data is based on the classical model of a mushy layer, which is modified in order to obtain analytical solutions in explicit form (so, for example, ice thickness and growth rate, temperature distributions, conductive and latent heat fluxes are determined). Furthermore, we find that the sea-ice growth is not simply a square-root function of time. It depends on the temperature variations in the atmosphere and lies between two square-root functions of time for the maximum and minimum temperatures found during observations. The theory under consideration is in good agreement with observations.

Os componentes do balanço de energia num solo cultivado com feijão caupi nas condições do Brejo Paraibano, foram determinados numa área de 4 ha do Centro de Ciências Agrárias, da UFPB, localizada no município de Areia, PB (6o 58' S, 35o 41' W e 620 m). Para tal, instalou-se uma torre no centro da área, contendo um pluviógrafo, um piranômetro, um saldo radiômetro e sensores para medida da temperatura e da umidade relativa do ar, em dois níveis acima do dossel da cultura; além disso, dois locais no solo foram instrumentados, cada um com duas sondas térmicas instaladas horizontalmente, nas profundidades de z1 = 2,0 cm e z2 = 8,0 cm, além de uma placa destinada à medida do fluxo de calor no solo, a 5,0 cm. Essas medidas foram armazenadas a cada 30 min, num sistema de aquisição de dados. Verificou-se que o valor médio do saldo de radiação (Rn) foi de 78%, sendo a Rn utilizada, em média, como 71% no fluxo de calor latente (LE), 19% como fluxo de calor sensível (H) e 10% como fluxo de calor no solo (G). A fração do saldo de radiação utilizada como fluxo de calor latente aumentou com a evolução da cobertura do solo pela cultura, enquanto a fração utilizada como fluxo de calor sensível e de calor no solo, diminuiu. The energy balance components in a cowpea crop growing in the mountain region of Paraiba, Brazil ("Brejo Paraibano") was determined in a 4 ha area in the Centro de Ciências Agrárias, UFPB, in the municipality of Areia, PB (6o 58' S, 35o 41' W e 620 m). Measurements of rainfall, net and global radiation were made. Sensors at two levels above the canopy were also mounted, allowing the measurements of air temperature and relative humidity. Below the soil surface, two different sites were provided with two thermal probes, horizontally installed at depths of 2.0 and 8.0 cm, besides a heat flux plate 5.0 cm deep for soil heat flux measurements. All data were stored in a datalogger each 30 min. The average value of the net radiation was 78% of the global solar radiation, in which 71% appeared as latent heat flux, 19% as sensible heat flux and 10% as soil heat flux. The fractional content of the latent heat flux in the net radiation increased as the soil covered by the crop increased, while the two other components decreased.

Submitted by Lucienne Costa (lucienneferreira@ufcg.edu.br) on 2019-05-14T20:04:38Z No. of bitstreams: 1 SÉRGIO CAVALCANTI DE PAIVA – DISSERTAÇÃO (PPGMET) 2005.pdf: 1112089 bytes, checksum: 5f730c6b7ed7657af5ee825858bd06c5 (MD5) Made available in DSpace on 2019-05-14T20:04:38Z (GMT). No. of bitstreams: 1 SÉRGIO CAVALCANTI DE PAIVA – DISSERTAÇÃO (PPGMET) 2005.pdf: 1112089 bytes, checksum: 5f730c6b7ed7657af5ee825858bd06c5 (MD5) Previous issue date: 2005-07-29 Capes Neste trabalho foram analisados aspectos do balanço de energia à superfície com ênfase aos fluxos de calor latente e sensível. Utilizaram-se dados observados da localidade de Petrolina-PE. Também, foram realizadas simulações com Brazilian Regional Atmospheric Modeling System – BRAMS para dois domínios de 50 por 50 pontos de grade com resoluções de 30 e de 5 km, centradas nas coordenadas 9º S e 40.5º W. Três períodos de cinco dias, com características de solo relativamente seco e de solo úmido, foram escolhidos para investigação. As análises se restringiram à grade aninhada, que dispõe de maior resolução espacial. As maiores limitações nas simulações foram a utilização da umidade do solo de forma homogênea, devido ao desconhecimento de dados observacionais na região, e a inexistência de observações micrometeorológicas para um período chuvoso. Os resultados comprovam que a energia disponível é majoritariamente utilizada como fluxo de calor latente para solo úmido e como fluxo de calor sensível para solo seco. Os valores observados dos fluxos de calores latente e sensível foram bem representados nas simulações. Nas simulações para solo relativamente seco observou-se indícios dos efeitos fisiográficos da região com destaque para a barragem de Sobradinho, o rio São Francisco e a orografia. Observa-se evaporação mais intensa sobre a barragem e ao longo do rio. Circulações locais tipo lacustre e vale-motanha são detectados pelos campos de advecção de umidade e de temperatura analisados. In this work, we analyzed the aspects of the energy balance at the surface, with emphasis on the latent and sensitive heat flux. The used data was observed in the location of Petrolina (a city in the state of Pernambuco, Brazil), and simulations were made using the Brazilian Regional Atmospheric Modeling System — BRAMS, for two domains of 50 by 50 points of grid with resolutions of 30 and 5 km, centered in the coordinates 9°S and 40.5°W. Three periods of five days in relatively dry soil, and in wet soil were chosen for the investigation. The analyses were limited to the higher resolution. The largest limitations in the simulations were the impossibility of using the moisture of the soil in a non-homogenous way, and the absence of micrometeorological measurements for a raining period. The results proved that the most part of available energy is used as latent heat flux for wet soil, and as sensitive heat flux for dry soil. The observed values of the latent and sensitive heat fluxes were well represented in the simulations. In the simulations for relatively dry soil, we observed indications of the physiographic effects in the region, with prominence for the Sobradinho Dam, the São Francisco River, and the orography. A more intense evaporation was observed in the Sobradinho dam and along the São Francisco River. Local circulations of the lacustre type and the mountain-valley type were detected by the advection fields of moisture and temperature analyzed.

Time series measurement of surface meteorological parameters using an Autonomous Weather Station and Moored Buoy positioned at 10.5 N and 72 E from July to November 2000 are used to compute latent heat flux (LHF) using COARE_3.0 algorithm for validating Special Sensor Microwave Imager (SSMI) derived LHF data. Mean positive and negative biases are observed between satellite and sea truth derived LHF estimates for summer (July to Sept) and inter-monsoon (Oct-Nov.) seasons respectively. Comparison during summer season exhibits very high correlation (> 75%) and is increasing progressively with longer climatologies. Satellite underestimates higher LHF values during summer while it overestimates lower LHF values in inter-monsoon season. Root Mean Square Deviation (RMSD) of LHF in summer is 12.5% of the highest value of 200 Wm -2 while it is 42 % of the mean lowest value of 50 Wm -2 during inter-monsoon season.

The variability of sensible and latent heat fluxes in the Mediterranean Sea and their effect on precipitation in the Greek area during the winter months are investigated for the 39 year period 1959-97 by using multivariate statistical methods. First, factor analysis is applied, mainly as a data reduction tool, and then canonical correlation analysis is applied on the factor scores time series of the two pairs, i.e. sensible heat flux-precipitation and latent heat flux-precipitation, to reveal their interrelations. The results show there is a statistically significant relationship between sensible and latent heat fluxes over the western Mediterranean Sea and precipitation in the western windward areas of Greece. The sensible and latent heat fluxes in the western Mediterranean Sea contribute significantly to depression development. The depressions formed advect cold and dry air masses over the western Mediterranean, reinforcing these sensible and latent heat fluxes. Furthermore, these depressions lead to a southerly or southwesterly airflow over Greece. This flow, along with the existence of potential instability, significantly contributes to precipitation formation in the windward areas of western Greece and also in the islands of the eastern Aegean Sea. Copyright (C) 2004 Royal Meteorological Society. International Journal of Climatology

Typical bogs in the boreal forest zone can be characterised by hummock and hollow micro-topography and sparsely vegetated surfaces. Their energy balance has been studied much less than for other types of surface, i.e. fields and forests. Micrometeorological measurements were carried out in central Sweden at two bogs in different summer seasons. From the measured profiles of wind speed, air temperature and humidity, the turbulent sensible and latent heat fluxes were calculated according to the Monin-Obukhov similarity theory. The daytime sensible and latent heat fluxes were typically of similar size, with the latent heat fluxes still being slightly higher. Independent measurements of turbulent, radiative and ground heat fluxes allowed to consider the surface energy balance closure. During fair weather conditions, the net radiation exceeded the sum of turbulent and ground heat fluxes by up to 200 W m-2 when measurements with ground heat flux plates were used in the analysis. It is difficult to attribute this discrepancy to errors in turbulent fluxes, because the fetch was long enough (400 m or more). Also, the size and shape of the two bogs and the positions of the tower were different, but the discrepancies in the energy budget were very similar. It is, however, known that measurements with heat flux plates in the peat are problematic. The ground heat flux measured with plates was very low and was considered to be the most unreliable component of the surface energy balance. An alternative method from the literature, which used temperature measurements in the peat and at the surface but did not require any information on the soil thermal properties near the surface, was used for alternative ground-heat-flux calculations. The use of this method improved the closure of the surface energy balance, but an about 100 W m-2 large discrepancy still remained unexplained. A further improvement is expected when lateral heat exchange in the hummocks could be taken into account.

Dados de saldo de radiação, fluxo de calor no solo, gradientes de temperatura e pressão do vapor, coletados no Campo Experimental da Embrapa Semi-Árido, em Petrolina, PE, foram utilizados na avaliação dos comportamentos diurno e sazonal dos componentes do balanço de energia, durante as fases fenológicas da cultura da banana, irrigada por microaspersão, no primeiro ano de produção. Em média, o saldo de radiação representou 63% da radiação solar global. A razão de Bowen foi utilizada na medição dos fluxos de calor latente e de calor sensível. A maior porção do saldo de radiação foi usada como fluxo de calor latente (87%) seguido pelo fluxo de calor no solo (11%) e pelo fluxo de calor sensível (2%). O baixo percentual do saldo de radiação usado como fluxo de calor sensível deve ser devido à advecção de umidade para a cultura proveniente do Rio São Francisco. Data of net radiation, soil heat flux, temperature and vapor pressure gradients, collected at Agrometeorology Experiment Station of Embrapa Semi-árido, at Petrolina, PE, Brazil, were used to evaluate the diurnal and seasonal beheavior of energy balance throughout the phenological phases of the banana crop in the first production cycle, irrigated by microaspersion. On average, the net radiation was 63% of the global solar radiation. The Bowen ratio was used to measure the latent and sensible fluxes. The higher portion of net radiation was utilized as latent heat flux (87%), followed by soil heat flux (11%) and by sensible heat flux (2%). The lower value of net radiation used as sensible heat flux may be because of the nearness of the São Francisco river that promoted humidity advection to the crop.

The energy exchange in the soil-snow-vegetation-atmospheresystem was studied to improve the quantitative knowledge of thegoverning processes. The lack of such knowledge contributes tothe uncertainty in the applicability of many existing modelsindependent of the temporal or spatial scale. The theoreticalbackground and available methods for measurements and numericalsimulations were reviewed. Numerical simulation models andavailable data sets representing open land and boreal forestwere evaluated in both diurnal and seasonal time-scales.Surface heat fluxes, snow depth, soil temperatures andmeteorological conditions were measured at an agriculturalfield in central Sweden over two winters, 1997-1999. Twoone-dimensional simulation models of different complexity wereused to simulate the heat and water transfer in thesoil-snow-atmosphere system and compared with the measurements.Comparison of simulated and observed heat fluxes showed thatparameter values governing the upper boundary condition weremore important than the formulation of the internal mass andheat balance of the snow cover. The models were useful toevaluate the lack of energy balance closure in the observedsurface heat fluxes, which underlined the importance ofimproved accuracy in eddy correlation measurements of latentflow during winter conditions. The representation of boreal forest in the land surfacescheme used within a weather forecast model was tested with athree-year data set from the NOPEX forest site in centralSweden. The formulation with separate energy balances forvegetation and the soil/snow beneath tree cover improvedsimulation of the seasonal and diurnal variations of latent andsensible heat flux compared with an older model version.Further improvements of simulated surface heat fluxes could beexpected if the variation of vegetation properties within andbetween years and a new formulation of the boundary conditionsfor heat flux into the soil is included. Keywords: Surface energy balance, Snow, Boreal forest,SVAT models, Eddy-correlation Measurements, Latent heat flux,Sensible heat flux, Net radiation, Soil temperature,Aerodynamic roughness, Surface resistance QC 20100614

The eddy covariance method is a viable method to measure evapotranspiration from tree and vine crops. However, one must be careful to measure properly the energy balance components and to apply corrections to the heat flux data to obtain good results. Based on several years of experience with energy balance measurements, we have found that failure to achieve the energy closure is often attributable to inaccurate soil heat flux density data. In addition, interference by wind blowing past the mounting tower can lead to spurious results. Although the benefit was small in our experiments, applying the corrections for air temperature and density changes (WPL) are recommended to eliminate errors in sensible and latent heat flux density. This is especially true for high elevations and for locations with extreme temperatures. We found that locating the net radiometer and the eddy covariance instruments above or between the rows seems to have little influence on the measurement as long as the sensors are not too close to the canopy elements indicating that the 'footprints' were not an important factor. In this paper, these aspects of measuring ET with the eddy covariance method and some results will be discussed.

Heat balance and radiation balance at the rooftop surface in urban area and the grass plot surface in suburban area of Hiroshima City were estimated on the basis of observation data in summer and winter. Difference in diurnal variation of energy balance between the rooftop surface and the grass plot surface was described preliminarily in this paper. As to the heat flux from the rooftop surface to the atmosphere, though the sensible heat flux is much larger than the latent heat flux in the afternoon, the latent heat flux is larger than the sensible heat flux in the morning. Therefore, the latent heat flux from the rooftop surface can not be disregarded. The sensible heat flux from the rooftop surface is larger than that from the grass plot surface during the daytime, which could cause higher temperature above the rooftop. Moreover, the heat flux into (daytime) / from (night) the inside of the building is larger than that into / from the soil of the grass plot especially in summer. This means that the heat storage of building is important for the energy balance of urban area in summer rather than in winter. Nighttime radiation cooling from the rooftop surface is stronger than that from the grass plot surface.

Large-scale measurements of land surface evaporation are required to develop techniques of integrating small-scale measurements into regional estimates of evaporation. These are necessary inputs into general circulation models that are used for weather forecasting (Mintz, 1984). They are also important for assessing and controlling water resources. Most of the techniques that have been developed over the years to estimate regional evaporation do not account for the heterogeneity in land-form, soil, and vegetative cover (Brutsaert, 1982). Interpretation of satellite data in combination with meteorological data represents a realistic approach for taking this heterogeneity into account and providing representative regional estimates of evaporation (Andre et al., 1986; Sellers et al., 1988). Regional near-surface observations of evaporation fluxes may serve to evaluate the usefulness of such remote sensing models. A direct and promising approach of obtaining near-surface evaporation estimates is from turbulent flux measurements of water vapor by the eddy correlation technique.

Heat balance and radiation balance at the rooftop surface in urban area and the grass plot surface in suburban area of Hiroshima City were estimated on the basis of observation data in summer and winter. Difference in diurnal variation of energy balance between the rooftop surface and the grass plot surface was described preliminarily in this paper. As to the heat flux from the rooftop surface to the atmosphere, though the sensible heat flux is much larger than the latent heat flux in the afternoon, the latent heat flux is larger than the sensible heat flux in the morning. Therefore, the latent heat flux from the rooftop surface can not be disregarded. The sensible heat flux from the rooftop surface is larger than that from the grass plot surface during the daytime, which could cause higher temperature above the rooftop. Moreover, the heat flux into (daytime) / from (night) the inside of the building is larger than that into / from the soil of the grass plot especially in summer. This means that the heat storage of building is important for the energy balance of urban area in summer rather than in winter. Nighttime radiation cooling from the rooftop surface is stronger than that from the grass plot surface.

Matter and energy flux dynamics of wetlands are important to understand environmental processes that govern biosphere-atmosphere interactions across ecosystems. This study presents analyses about hourly interaction between wind speed and energy fluxes in Brazilian Wetlands - Mato Grosso - Brazil. This study was conducted in Private Reserve of Natural Heritage (PRNH SESC, 16º39'50''S; 56º47'50''W) in Brazilian Wetland. According to Curado et al. (2012), the wet season occurs between the months of January and April, while the June to September time period is the dry season. Results presented same patterns in energies fluxes in all period studied. Wind speed and air temperature presented same patterns, while LE was relative humidity presented inverse patterns of the air temperature. LE was predominant in all seasons and the sum of LE and H was above 90% of net radiation. Analyses of linear regression presented positive interactions between wind speed and LE, and wind speed and H in all seasons, except in dry season of 2010. Confidence coefficient regression analyses present statistical significance in all wet and dry seasons, except dry season of 2010, suggest that LE and H had interaction with other micrometeorological variables.

This study examines how land-use errors from the Land Transformation Model (LTM) propagate through to climate as simulated by the Regional Atmospheric Model System (RAMS). The authors conducted five simulations of regional climate over East Africa: one using observed land cover/land use (LULC) and four utilizing LTM-derived LULC. The study examined how quantifiable errors generated by the LTM impact typical land–climate variables: precipitation, land surface temperature, air temperature, soil moisture, and latent heat flux. Error propagation was not evident when domain averages for the land–climate variables of the yearlong simulation were examined. However, the authors found that spatial errors from the LTM propagate through in complex ways, temporally affecting the seasonal distributions of rainfall, surface temperature, soil moisture, and latent heat flux. In particular, rainy seasons exhibited greater precipitation in LTM-RAMS simulations than in the reference simulation and less precipitation occurred during the dry season. Complex interactions of precipitation and soil moisture were also evident. Overall, results indicate that small errors from a land change model could grow as a “coupling drift” if both are used to forecast into the future; these couplings could create larger combined errors of land–climate interactions because of time-scale differences into the future. Thus, although land-use change projection is necessary for a more accurate climate projection, existing errors from a land change model will likely amplify through the climate simulation. This finding affects interpretation of large-scale versus land-use/land-cover feedbacks on climate projections.

Vegetation cover and groundwater level changes over the period of restoration are the two most important indicators of the level of success in wetland ecohydrological restoration. As a result of the regular presence of water and dense vegetation, the highest evapotranspiration (latent heat) rates usually occur within wetlands. Vegetation cover and evapotranspiration of large areas of restoration like that of Kissimmee River basin, South Florida will be best estimated using remote sensing technique than point measurements. Kissimmee River basin has been the area of ecological restoration for some years. The current ecohydrological restoration activities were evaluated through fractional vegetation cover (FVC) changes and latent heat flux using Moderate Resolution Imaging Spectroradiometer (MODIS) data. Groundwater level data were also analyzed for selected eight groundwater monitoring wells in the basin. Results have shown that the average fractional vegetation cover and latent heat along 10 km buffer of Kissimmee River between Lake Kissimmee and Lake Okeechobee was higher in 2004 than in 2000. It is evident that over the 5-year period of time, vegetated and areas covered with wetlands have increased significantly especially along the restoration corridor. Analysis of groundwater level data (2000-2004) from eight monitoring wells showed that, the average monthly level of groundwater was increased by 20 cm and 34 cm between 2000 and 2004, and 2000 and 2003, respectively. This change was more evident for wells along the river.