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Grant L. Harley, James King, and Justin T. Maxwell

-derived increase in aerosol optical depth (AOD) and subsequent reduced total PAR was the mechanism responsible for triggering the production of the IADF in P. elliottii during the peak of the 2010 growing season (July). 2. Materials and methods We analyzed Earth Observation (EO) products available from NASA, surface meteorological measurements, and modeled irradiance data to reveal a relationship between dust-derived changes in AOD and atmospheric conditions at the surface in southern Florida. Tree growth

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Arindam Samanta, Sangram Ganguly, Eric Vermote, Ramakrishna R. Nemani, and Ranga B. Myneni

aerosol optical thickness (AOT) was obtained from the level 3 daily joint aerosol/water vapor/cloud product (MOD08_D3) at 1° × 1° spatial resolution. These were obtained from the NASA Level 1 and Atmosphere Archive and Distribution System (LAADS) ( NASA 2011a ) for the months of July–September of the years 2000–06. We used the optical_depth_land_and_ocean_mean_mean data field from this product, which contains AOT at 550 nm. Similarly, monthly AOT was obtained from the level 3 monthly joint aerosol

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D. Rind and X. Liao

humidity values have also been calculated from the water vapor mixing ratio and the NMC temperature data. The column-integrated stratospheric optical thickness at 1020 nm, down to 2 km above the tropopause, is shown as well. Though the gridded data and images were created for a quick scan of monthly retrievals, the data may not provide a true monthly average due to the sparse number of observations. Users should be aware of this when interpreting the data results and should consult the observation

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Peiyun Zhu, Susan J. Cheng, Zachary Butterfield, Gretchen Keppel-Aleks, and Allison L. Steiner

), the response of plant canopy carbon uptake to different cloud conditions has not been constrained by observations on a global scale. The effect of clouds on surface radiation can be quantitatively described with a global metric of cloud optical thickness (COT; τ c )—a dimensionless variable that captures the reduction in solar radiation per unit cloud pathlength z : (1) τ c = ∫ 0 d β ⁡ ( z ) d z , where d is the height of the cloud and β is the cloud extinction coefficient ( Mayer et al

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Gregory P. Asner, David E. Knapp, Amanda N. Cooper, Mercedes M. C. Bustamante, and Lydia P. Olander

program is integrated into the CLAS processing stream and uses average monthly aerosol optical thickness (AOT) and water vapor (WV) values from the NASA MODIS sensor. Time stamping of MODIS AOT and WV with Landsat data is done on an automated basis ( Figure 3 ). A series of masks are designed to exclude clouds, water bodies, cloud shadows, and nonimage areas from the analysis. These masks are derived directly from the raw and calibrated Landsat imagery as well as from the AutoMCU submodel output of

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Walter N. Meier, James A. Maslanik, Charles W. Fowler, and Jeffrey R. Key

(fractional coverage, optical depth, phase, particle effective radius, temperature, and cloud height), downwelling radiative fluxes, and ice motion vectors. The basic approach and portions of the product set are described, and sample applications are included to illustrate possible uses of the datasets. These products represent a preliminary step in the development of similar products for the entire Arctic and Antarctic regions as part of the National Aeronautics and Space Administration (NASA) Pathfinder

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Ansar Khan, Samiran Khorat, Rupali Khatun, Quang-Van Doan, U. S. Nair, and Dev Niyogi

used as a reference to analyze the impact of COVID-19 lockdown on urban air quality across India in this premonsoon period. 2. Materials and methods We utilized the daily mean values of air quality index (AQI) and concentrations of seven criteria air pollutants (PM 2.5 , PM 10 , O 3 , SO 2 , NO 2 , NH 3 , and CO) from 91 cities ( Fig. 1 ). The time of interest for this study is from 18 March to 17 May 2020, and the corresponding days of 2019. We also used satellite retrievals of aerosol optical

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Maria de Lourdes Pinheiro Ruivo, José Augusto Pereira Barreiros, Alexandre Bragio Bonaldo, Rosecélia Moreira da Silva, Leonardo Deane Abreu Sá, and Elessandra Laura Nogueira Lopes

carbon per volumetric unit of soil (kg C m −2 ) using bulk density values and layers thickness. 2.4. Microbiology analysis The number of bacteria and fungi was determined for the former’s units of colonies, using the “pour plate” technique of counting in Petri dishes with assistance from the Colonies Counter CP-602. The predominant colonies were isolated and then microscopic preparations were made to study morphological characters in optical microscopy. 2.5. Litter spider fauna Four expeditions were

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M. Rodell, B. F. Chao, A. Y. Au, J. S. Kimball, and K. C. McDonald

comparison of these results with microwave optical thickness maps derived from mean monthly brightness temperature data from the Advanced Microwave Scanning Radiometer for EOS (AMSR-E) on board the NASA Aqua satellite yielded similar spatial patterns and general relationships among global land-cover class, microwave optical thickness, and vegetation water content (E. Njoku, Jet Propulsion Laboratory, California Institute of Technology, 2003, personal communication). 5. Summary Global maps of vegetation

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Mohammad H. Mokhtari, Ibrahim Busu, Hossein Mokhtari, Gholamreza Zahedi, Leila Sheikhattar, and Mohammad A. Movahed

), spatiotemporal interpolation of climatic variables ( Antonić et al. 2001 ), and estimation of spatially varying albedo and optical thickness in radiation slab ( Bokar 1999 ). The applicability of these methods in selecting the best variables and predicting dependent variables has been proved where a limited number of input variables are available ( Konno and Takaya 2008 ; Kisi 2007 ; Jain et al. 2008 ; Rahimi Khoob 2009 ). Likewise, a neural network has been identified as an efficient technique for

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