Effect of the satellite spatial resolution on the surface energy fluxes retrieval. Application to the Basilicata Italian Region

Remote sensing estimates of the surface energy balance, and daily evapotranspiration (LEd) in particular, have become essential in recent studies on climatology,meteorology and hydrology. High spatial resolution satellites such as Landsat or ASTER provide surface information at pixel resolutions on the order or below100 m, but the low frequency of repeated coverage limits the utility of these sensors in the routine monitoring of LEd. Daily coverage is provided by regional to global sensors such as MODIS (1000 m) or METEOSAT (5000 m). However, most of the surface variability is lost at these coarse spatial resolutions. Recent studies have explored the possibility to estimate subpixel energy fluxes, at the spatial resolution of the sensor visible bands, to recover the mentioned surface variability. In this work, it has been firstly evaluated the loss of information in surface temperature variability with the degradation of the spatial resolution of a satellite image. Secondly, a disaggregation procedure to estimate subpixel surface temperatures has been applied at different spatial resolutions. Finally, a Simplified Two-Source Energy Balance (STSEB) model has been used to evaluate the effect of the disaggregation technique on the surface fluxes retrieval. Three satellite images of the Basilicata southern Italian region, Landsat7-ETM+, Landsat5-TM and MODIS Terra have been used. Three different targets were selected within each image in order to analyze the effect of the field size on the obtained results

Sviluppo di una procedura integrata di analisi per la stima dell’evapotraspirazione reale

Nel presente lavoro viene sviluppata una procedura integrata di analisi per la stima dell’evapotraspirazione reale, basata sull’integrazione di dati di campo e dati da satellite, e successivamente applicata al territorio della regione Basilicata. I dati di campo utilizzati, relativi a velocità del vento, temperatura dell’aria e radiazione globale, derivano dalle stazioni agro-meteorologiche dell’ALSIA (Agenzia Lucana di Sviluppo ed Innovazione in Agricoltura), distribuite più o meno uniformemente sul territorio della regione, mentre i dati da satellite, riguardanti i flussi di energia superficiale e la distribuzione della vegetazione sul territorio oggetto di studio, sono ricavati dall’elaborazione di tre immagini satellitari ad alta risoluzione, rilevate dai sensori TM (Thematic Mapper) ed ETM+ (Enhanced Thematic Mapper Plus), a bordo, rispettivamente, dei satelliti Landsat-5 e Landsat-7. Inoltre, per la correzione dei dati satellitari vengono utilizzati profili atmosferici da radiosonda. Per la schematizzazione della resistenza effettiva del sistema suolo-vegetazione-atmosfera si fa riferimento ad un modello in parallelo, proposto da Sánchez et al. (2005), secondo il quale la ripartizione del flusso di calore sensibile totale tra suolo e vegetazione è ponderata sulla base della distribuzione degli stessi nell’area di studio. Viene invece applicato un bilancio tra radiazione ad onda lunga e ad onda corta per ricavare il flusso di radiazione netta. A partire dalla mappa tematica di uso del suolo CORINE Land Cover della Basilicata, si procede, per mappe tematiche successive, a determinare e rappresentare la distribuzione di vegetazione, l’emissività, il flusso di calore sensibile e la radiazione netta, ottenendo, infine, l’evapotraspirazione reale, a scala giornaliera, come termine residuale dell’equazione del bilancio energetico. Dalla mappa finale di evapotraspirazione reale vengono estratti alcuni valori per uso del suolo e confrontati con le corrispondenti misure di campo, realizzate presso alcune località italiane, inserite nel progetto integrato europeo CARBOEUROPE, mostrando una buona corrispondenza tra i valori sperimentali e quelli ricavati con la metodologia proposta

Pixel-oriented land use classification in energy balance modelling

Mass and energy transfer between soil-vegetation and the atmosphere is the process that allows to maintain an adequate energy and water balance in the earth-atmosphere system. However, the evaluation of the energy balance components, such as the net radiation and sensible and latent heat fluxes, is characterized by significant uncertainties related both to the dynamic nature of heat transfer processes and surfaces heterogeneity. Therefore, a detailed land use classification and an accurate evaluation of vegetation spatial distribution are required for an accurate estimation of these variables. For this purpose, in the present paper, a pixel-oriented supervised classification was applied to obtain land use maps of the Basilicata region, in Southern Italy, by processing three Landsat TM and ETM+ satellite images. An accuracy analysis based on the overall accuracy index and the agreement Khat of Cohen coefficient showed a good performance of the applied classification methodology and a good quality of the obtained maps. Subsequently, these maps were used in the application of a Simplified Two-Source Energy Balance (STSEB) model for estimating the actual evapotranspiration at a regional scale. The comparison between the simulations made by applying the STSEB model and the measurements of evapotranspiration at a lysimetric station located in the study area showed the applicability and validity of the proposed methodology

Efficacy and safety of pregabalin in patients with fibromyalgia and comorbid depression taking concurrent antidepressant medication: A randomized, placebo-controlled study

Objective. To assess pregabalin efficacy and safety in patients with fibromyalgia (FM) with comorbid depression taking concurrent antidepressant medication. Methods. This randomized, placebo-controlled, double-blind, 2-period, 2-way crossover study was composed of two 6-week treatment periods separated by a 2-week taper/washout phase. Patients with FM (aged 65 18 yrs) taking a stable dose of a selective serotonin reuptake inhibitor (SSRI) or a serotonin/norepinephrine reuptake inhibitor (SNRI) for depression were randomized 1:1 to receive pregabalin/placebo or placebo/pregabalin (optimized to 300 or 450 mg/day). Antidepressant medication was continued throughout the study. The primary efficacy outcome was the mean pain score on an 11-point numerical rating scale. Secondary efficacy outcomes included measures of anxiety, depression, patient function, and sleep. Results. Of 197 patients randomized to treatment, 181 and 177 received 65 1 dose of pregabalin and placebo, respectively. At baseline, 52.3% of patients were taking an SSRI and 47.7% an SNRI, and mean pain score was 6.7. Mean pain scores at endpoint were statistically significantly reduced with pregabalin (least squares mean difference from placebo-0.61, 95% CI-0.91-0.31, p = 0.0001). Pregabalin significantly improved Hospital Anxiety and Depression Scale-Anxiety (difference-0.95, p < 0.0001) and-Depression (difference-0.88, p = 0.0005) scores, Fibromyalgia Impact Questionnaire total score (difference-6.60, p < 0.0001), and sleep quality (difference 0.57, p < 0.0001), but not EuroQol 5-Dimensions score (difference 0.02, p = 0.3854). Pregabalin safety was consistent with previous studies and current product labeling. Conclusion. Compared with placebo, pregabalin statistically significantly improved FM pain and other symptoms in patients taking antidepressant medication for comorbid depression