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Full-Text Articles in Engineering
Potential Significance Of Photoexcited No2 On Global Air Quality With The Nmmb/Bsc Chemical Transport Model, O. Jorba, D. Dabdub, Christopher S. Blaszczak-Boxe, C. Pérez, Z. Janjic, J. M. Baldasano, M. Spada, A. Badia, M. Gonçalves
Potential Significance Of Photoexcited No2 On Global Air Quality With The Nmmb/Bsc Chemical Transport Model, O. Jorba, D. Dabdub, Christopher S. Blaszczak-Boxe, C. Pérez, Z. Janjic, J. M. Baldasano, M. Spada, A. Badia, M. Gonçalves
Publications and Research
Atmospheric chemists have recently focused on the relevance of the NO2* + H2O → OH + HONO reaction to local air quality. This chemistry has been considered not relevant for the troposphere from known reaction rates until nowadays. New experiments suggested a rate constant of 1.7 × 10−13 cm3 molecule−1 s−1, which is an order of magnitude faster than the previously estimated upper limit of 1.2 × 10−14 cm3 molecule−1 s−1, determined by Crowley and Carl (1997). Using the new global model, NMMB/BSC Chemical Transport Model (NMMB/BSC-CTM), simulations are presented that assess the potential significance of this chemistry on global …
Validation Of Noaa-Interactive Multisensor Snow And Ice Mapping System (Ims) By Comparison With Ground-Based Measurements Over Continental United States, Christine Chen, Tarendra Lakhankar, Peter Romanov, Sean Helfrich, Al Powell, Reza Khanbilvardi
Validation Of Noaa-Interactive Multisensor Snow And Ice Mapping System (Ims) By Comparison With Ground-Based Measurements Over Continental United States, Christine Chen, Tarendra Lakhankar, Peter Romanov, Sean Helfrich, Al Powell, Reza Khanbilvardi
Publications and Research
In this study, daily maps of snow cover distribution and sea ice extent produced by NOAA’s interactive multisensor snow and ice mapping system (IMS) were validated using in situ snow depth data from observing stations obtained from NOAA’s National Climatic Data Center (NCDC) for calendar years 2006 to 2010. IMS provides daily maps of snow and sea ice extent within the Northern Hemisphere using data from combination of geostationary and polar orbiting satellites in visible, infrared and microwave spectrums. Statistical correspondence between the IMS and in situ point measurements has been evaluated assuming that ground measurements are discrete and continuously …
Using Avhrr-Based Vegetation Health Indices For Estimation Of Potato Yield In Bangladesh, Rahman A., Kaiser Khan, Nir Y. Krakauer, Leonid Roytman, Kogan F.
Using Avhrr-Based Vegetation Health Indices For Estimation Of Potato Yield In Bangladesh, Rahman A., Kaiser Khan, Nir Y. Krakauer, Leonid Roytman, Kogan F.
Publications and Research
We developed a model correlating Advanced Very High Resolution Radiometer (AVHRR)-based Temperature Condition Index (TCI) and Vegetation Condition Index (VCI) with potato yield in Bangladesh. Weekly TCI and VCI Indices for 1993–2005 along with official potato yield statistics were used for model development. We found a strong correlation between inter annual variation in potato yield and TCI and VCI during the critical period of potato growth (vegetative phase and tuber initiation), mid-December to mid-January. Principal component regression (PCR) was used to construct a model to predict potato yield as function of TCI and VCI. The model explained about 75% of …
Using Microwave Brightness Temperature Diurnal Cycle To Improve Emissivity Retrievals Over Land, Hamidreza Norouzi, William Rossow, Marouane Temimi, Catherine Prigent, Marzieh Azarderakhsh, Sid Boukabara, Reza Khanbilvardi
Using Microwave Brightness Temperature Diurnal Cycle To Improve Emissivity Retrievals Over Land, Hamidreza Norouzi, William Rossow, Marouane Temimi, Catherine Prigent, Marzieh Azarderakhsh, Sid Boukabara, Reza Khanbilvardi
Publications and Research
To retrieve microwave land emissivity, infrared surface skin temperatures have been used as surface physical temperature since there is no global information on physical vegetation/soil temperature profiles. However, passive microwave emissions originate fromdeeper layerswith respect to the skin temperature. So, this inconsistency in sensitivity depths between skin temperatures and microwave temperaturesmay introduce a discrepancy in the determined emissivity. Previous studies showed that this inconsistency can lead to significant differences between day and night retrievals of land emissivity which can exceed 10%. This study proposes an approach to address this inconsistency and improve the retrieval of land emissivity using microwave observations …
Analysis Of The Effects Of Snowpack Properties On Satellite Microwave Brightness Temperature And Emissivity Data, Tarendra Lakhankar, Amir E. Azar, Narges Shahroudi, Alfred Powell, Reza Khanbilvardi
Analysis Of The Effects Of Snowpack Properties On Satellite Microwave Brightness Temperature And Emissivity Data, Tarendra Lakhankar, Amir E. Azar, Narges Shahroudi, Alfred Powell, Reza Khanbilvardi
Publications and Research
Spatial variations of snowpack properties are an essential component in flood predictions and water resource management. Satellite microwave remote sensing has shown great potential in retrieving snowpack properties such as: snow depth, snow grain size, and snow density. In this research, we investigate the potential of microwave emissivity which is highly influenced by snowpack properties. Brightness temperature and emissivity data generated from HUT (Helsinki University of Technology) microwave emission of snow model were evaluated with satellite microwave measurements. The comparison of the real measurements (in-situ and satellite) with the modeled results shows that the scattering signature (19GHz-37GHz and 19GHz-85GHz) shows …