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Full-Text Articles in Physical Sciences and Mathematics

Quo Vadis Lakes Azuei And Enriquillo: A Future Outlook For Two Of The Caribbean Basin's Largest Lakes, Mahrokh Moknatian, Michael Piasecki Jul 2021

Quo Vadis Lakes Azuei And Enriquillo: A Future Outlook For Two Of The Caribbean Basin's Largest Lakes, Mahrokh Moknatian, Michael Piasecki

Publications and Research

Lakes Azuei (LA) and Enriquillo (LE) on Hispaniola Island started expanding in 2005 and continued to do so until 2016. After inundating large swaths of arable land, submerging a small community, and threatening to swallow a significant trade route between the Dominican Republic and Haiti; worries persisted at how far this seemingly unstoppable expansion would go. The paper outlines the approach to a look forward to answer this question vis-à-vis climate change scenarios developed by the Intergovernmental Panel on Climate Change (IPCC). It uses numerical representations of the two lakes, and it examines how the lakes might evolve, deploying three …


Lake Volume Data Analyses: A Deep Look Into The Shrinking And Expansion Patterns Of Lakes Azuei And Enriquillo, Hispaniola, Mahrokh Moknatian, Michael Piasecki Jan 2020

Lake Volume Data Analyses: A Deep Look Into The Shrinking And Expansion Patterns Of Lakes Azuei And Enriquillo, Hispaniola, Mahrokh Moknatian, Michael Piasecki

Publications and Research

This paper presents the development of an evenly spaced volume time series for Lakes Azuei and Enriquillo both located on the Caribbean island of Hispaniola. The time series is derived from an unevenly spaced Landsat imagery data set which is then exposed to several imputation methods to construct the gap filled uniformly‐spaced time series so it can be subjected to statistical analyses methods. The volume time series features both gradual and sudden changes the latter of which is attributed to North Atlantic cyclone activity. Relevant cyclone activity is defined as an event passing within 80 km and having regional monthly …


Land Surface Temperature Variability Across India: A Remote Sensing Satellite Perspective, Satya Prakash, Hamidreza Norouzi Nov 2019

Land Surface Temperature Variability Across India: A Remote Sensing Satellite Perspective, Satya Prakash, Hamidreza Norouzi

Publications and Research

Land surface temperature (LST) plays a key role in the surface energy budget computation and land surface process studies. The Moderate Resolution Imaging Spectroradiometer (MODIS) sensors onboard the Aqua and Terra satellites provide comprehensive global LST estimates at a fine spatial resolution. The MODIS products were recently upgraded to Collection 6, and shown to be more accurate than its predecessor Collection 5 products. In this study, LST and its variability have been examined across India from Collection 6 of the Aqua MODIS data at 0.05° spatial resolution for the period of 2003 to 2017. All-India mean LST characteristics show distinctive …


Development Of Digital Bathymetry Maps For Lakes Azuei And Enriquillo Using Sonar And Remote Sensing Techniques, Michael Piasecki, Mahrokh Moknatian, Fred Moshary, Jorge Gonzalez May 2019

Development Of Digital Bathymetry Maps For Lakes Azuei And Enriquillo Using Sonar And Remote Sensing Techniques, Michael Piasecki, Mahrokh Moknatian, Fred Moshary, Jorge Gonzalez

Publications and Research

This article presents an improved algorithm for optimization and development of a digital bathymetric model (DBM) for Lake Azuei (LA) (Haiti) and Lake Enriquillo (LE) (Dominican Republic) using the ANUDEM method. Both sonar data and contour lines of the lakes’ layout extracted using Landsat imagery were compiled for bathymetry development. We show that the performance of the ANUDEM method was strongly dependent on the density and irregularity of the spatial distribution of the data. Changing the resolution of the output grids and deriving auxiliary topographically corrected contours improved the ANUDEM performance and minimized the systematic errors of the method. Statistical …


Observational Time Series For Lakes Azuei And Enriquillo: Surface Area, Volume, And Elevation, Mahrokh Moknatian, Michael Piasecki Jan 2019

Observational Time Series For Lakes Azuei And Enriquillo: Surface Area, Volume, And Elevation, Mahrokh Moknatian, Michael Piasecki

Publications and Research

In this report, we present historical time series of surface area, volume, and elevation for lakes Azuei (Haiti) and Enriquillo (Dominican Republic). The intention is to present a history of the lakes’ levels for both bodies of water as derived from Landsat imagery that is augmented by reports and narratives that reach further back in time. We also summarize lake level time series data collected and developed through various other efforts and compare these data sets to our time series. The time series contains 45 years’ worth of data ranging from 1972 to 2017 which we developed from Landsat imagery …


An Overview Of Smartwater Management System: Strategic Potential In Bangladesh, Muhammad Qumrul Hassan, Mir F. Karim, Nazrul I. Khandaker, Jowaher Raza Nov 2018

An Overview Of Smartwater Management System: Strategic Potential In Bangladesh, Muhammad Qumrul Hassan, Mir F. Karim, Nazrul I. Khandaker, Jowaher Raza

Publications and Research

Water loss management is becoming an increasingly important as supplies are stressed by population growth or water scarcity. A SmartWater system ensures optimum consumption and prediction of future water use. Bangladesh is one of the most vulnerable countries due to global climate change considering its rapid urbanization, inequitable land use, low income and greater reliance on climate sensitive sectors, particularly agriculture. Agricultural lands used for cropping and livestock rearing are more susceptible to degradation than non-agricultural lands. Most farmers irrigate through flooding, losing up to 75% of water to evaporation and creating a substantial drawdown of much needed water for …


Season-Ahead Forecasting Of Water Storage And Irrigation Requirements – An Application To The Southwest Monsoon In India, Arun Ravindranath, Naresh Devineni, Upmanu Lall, Paulina Concha Larrauri Oct 2018

Season-Ahead Forecasting Of Water Storage And Irrigation Requirements – An Application To The Southwest Monsoon In India, Arun Ravindranath, Naresh Devineni, Upmanu Lall, Paulina Concha Larrauri

Publications and Research

Water risk management is a ubiquitous challenge faced by stakeholders in the water or agricultural sector. We present a methodological framework for forecasting water storage requirements and present an application of this methodology to risk assessment in India. The application focused on forecasting crop water stress for potatoes grown during the monsoon season in the Satara district of Maharashtra. Pre-season large-scale climate predictors used to forecast water stress were selected based on an exhaustive search method that evaluates for highest ranked probability skill score and lowest root-mean-squared error in a leave-one-out cross-validation mode. Adaptive forecasts were made in the years …


Recent Trends In The Frequency And Duration Of Global Floods, Nasser Najibi, Naresh Devineni Jun 2018

Recent Trends In The Frequency And Duration Of Global Floods, Nasser Najibi, Naresh Devineni

Publications and Research

Frequency and duration of floods are analyzed using the global flood database of the Dartmouth Flood Observatory (DFO) to explore evidence of trends during 1985–2015 at global and latitudinal scales. Three classes of flood duration (i.e., short: 1–7, moderate: 8–20, and long: 21 days and above) are also considered for this analysis. The nonparametric Mann–Kendall trend analysis is used to evaluate three hypotheses addressing potential monotonic trends in the frequency of flood, moments of duration, and frequency of specific flood duration types. We also evaluated if trends could be related to large-scale atmospheric teleconnections using a generalized linear model framework. …


Bathymetry Data For Lakes Azuei And Enriquillo, Michael Piasecki, Mahrokh Moknatian Feb 2018

Bathymetry Data For Lakes Azuei And Enriquillo, Michael Piasecki, Mahrokh Moknatian

Publications and Research

This data set supports and forms the basis for the development of Digital Bathymetry Models (DBM) for Lakes Azuei (Haiti) and Enriquillo (Dominican Republic). Bathymetric Data is typically acquired using Sonar devices that measure the depth at specific points along a boat track and for which the longitude and latitude is recorded. From the resulting point cloud one develop a seamless representation of the floor of the lake on either a raster set (which is what we have done) or try to use a contour (vector representation) model in which the depth contours appear as polygons or -lines. The raw …


Computational Methods In Civil Engineering, Nir Krakauer Jan 2018

Computational Methods In Civil Engineering, Nir Krakauer

Open Educational Resources

No abstract provided.


Assessment Of Differences Between Near-Surface Air And Soil Temperatures For Reliable Detection Of High-Latitude Freeze And Thaw States, Farjana Shati, Satya Prakash, Hamid Norouzi, Reginald Blake Oct 2017

Assessment Of Differences Between Near-Surface Air And Soil Temperatures For Reliable Detection Of High-Latitude Freeze And Thaw States, Farjana Shati, Satya Prakash, Hamid Norouzi, Reginald Blake

Publications and Research

Near-surface air temperature and the underlying soil temperature are among the key components of the Earth’s surface energy budget, and they are important variables for the comprehensive assessment of global climate change. Better understanding of the difference in magnitude between these two variables over high-latitude regions is also crucial for accurate detections of freeze and thaw (FT) states. However, these differences are not usually considered and included in current remote sensing-based FT detection algorithms. In this study, the difference between near-surface air temperature at the 2-meter height and soil temperature at the 5-centimeter depth is assessed using ground-based observations that …


Development Of Geospatial And Temporal Characteristics For Hispaniola’S Lake Azuei And Enriquillo Using Landsat Imagery, Mahrokh Moknatian, Michael Piasecki, Jorge Gonzalez May 2017

Development Of Geospatial And Temporal Characteristics For Hispaniola’S Lake Azuei And Enriquillo Using Landsat Imagery, Mahrokh Moknatian, Michael Piasecki, Jorge Gonzalez

Publications and Research

In this paper, we used Landsat imagery for water body identification to create a novel 36-year surface area extent time series for lakes Azuei (Haiti) and Enriquillo (Dominican Republic) aimed at illuminating the dramatic temporal changes of these two lakes not just at yearly but at monthly or even sub-monthly scales. We used the Normalized Difference Water Index (NDWI) to extract water features and we also used spatial differentiation and thresholding techniques to remove clouds and associated shadows from the scene that were then passed through gap filling algorithms to complete and extract the lake extent polygons. We also explored …


Proof Of Concept: Development Of Snow Liquid Water Content Profiler Using Cs650 Reflectometers At Caribou, Me, Usa, Carlos L. Pérez Díaz, Jonathan Muñoz, Tarendra Lakhankar, Reza Khanbilvardi, Peter Romanov Mar 2017

Proof Of Concept: Development Of Snow Liquid Water Content Profiler Using Cs650 Reflectometers At Caribou, Me, Usa, Carlos L. Pérez Díaz, Jonathan Muñoz, Tarendra Lakhankar, Reza Khanbilvardi, Peter Romanov

Publications and Research

The quantity of liquid water in the snowpack defines its wetness. The temporal evolution of snow wetness’s plays a significant role in wet-snow avalanche prediction, meltwater release, and water availability estimations and assessments within a river basin. However, it remains a difficult task and a demanding issue to measure the snowpack’s liquid water content (LWC) and its temporal evolution with conventional in situ techniques. We propose an approach based on the use of time-domain reflectometry (TDR) and CS650 soil water content reflectometers to measure the snowpack’s LWC and temperature profiles. For this purpose, we created an easily-applicable, low-cost, automated, and …


A Comparison Of Modis/Viirs Cloud Masks Over Ice-Bearing River: On Achieving Consistent Cloud Masking And Improved River Ice Mapping, Simon Kraatz, Reza Khanbilvardi, Peter Romanov Mar 2017

A Comparison Of Modis/Viirs Cloud Masks Over Ice-Bearing River: On Achieving Consistent Cloud Masking And Improved River Ice Mapping, Simon Kraatz, Reza Khanbilvardi, Peter Romanov

Publications and Research

The capability of frequently and accurately monitoring ice on rivers is important, since it may be possible to timely identify ice accumulations corresponding to ice jams. Ice jams are dam-like structures formed from arrested ice floes, and may cause rapid flooding. To inform on this potential hazard, the CREST River Ice Observing System (CRIOS) produces ice cover maps based on MODIS and VIIRS overpass data at several locations, including the Susquehanna River. CRIOS uses the respective platform’s automatically produced cloud masks to discriminate ice/snow covered grid cells from clouds. However, since cloud masks are produced using each instrument’s data, and …


Ocean–Atmosphere Interactions Modulate Irrigation’S Climate Impacts, Nir Y. Krakauer, Michael J. Puma, Benjamin I. Cook, Pierre Gentine, Larisa Nazarenko Nov 2016

Ocean–Atmosphere Interactions Modulate Irrigation’S Climate Impacts, Nir Y. Krakauer, Michael J. Puma, Benjamin I. Cook, Pierre Gentine, Larisa Nazarenko

Publications and Research

Numerous studies have focused on the local and regional climate effects of irrigated agriculture and other land cover and land use change (LCLUC) phenomena, but there are few studies on the role of ocean– atmosphere interaction in modulating irrigation climate impacts. Here, we compare simulations with and without interactive sea surface temperatures of the equilibrium effect on climate of contemporary (year 2000) irrigation geographic extent and intensity.We find that ocean–atmosphere interaction does impact the magnitude of globalmean and spatially varying climate impacts, greatly increasing their global reach. Local climate effects in the irrigated regions remain broadly similar, while non-local effects, …


Bathymetric Survey For Lakes Azuei And Enriquillo, Hispaniola, Michael Piasecki, Mahrokh Moknatian, Fred Moshary, Joseph Cleto, Yolanda Leon, Jorge Gonzalez, Daniel Comarazamy Jun 2016

Bathymetric Survey For Lakes Azuei And Enriquillo, Hispaniola, Michael Piasecki, Mahrokh Moknatian, Fred Moshary, Joseph Cleto, Yolanda Leon, Jorge Gonzalez, Daniel Comarazamy

Publications and Research

The two largest lakes on the Caribbean Island of Hispaniola, Lake Azuei in Haiti and Lake Enriquillo in the Dominican Republic, have experienced dramatic growth and surface area expansion over the past few years leading to severe flooding and loss of arable land around the lake perimeters. In order to better understand the reasons for this unprecedented rate of expansion and the resulting consequences a multi-disciplinary team comprised of researchers from Haiti, the DR, and the US have embarked on an extensive data collecting and hydrologic and climatological modeling campaign. While the sensor deployment entails stations that measure climatological data …


Historical Trends In Mean And Extreme Runoff And Streamflow Based On Observations And Climate Models, Behzad Asadieh, Nir Y. Krakauer, Balázs M. Fekete May 2016

Historical Trends In Mean And Extreme Runoff And Streamflow Based On Observations And Climate Models, Behzad Asadieh, Nir Y. Krakauer, Balázs M. Fekete

Publications and Research

To understand changes in global mean and extreme streamflow volumes over recent decades, we statistically analyzed runoff and streamflow simulated by the WBM-plus hydrological model using either observational-based meteorological inputs from WATCH Forcing Data (WFD), or bias-corrected inputs from five global climate models (GCMs) provided by the Inter-Sectoral Impact Model Intercomparison Project (ISI-MIP). Results show that the bias-corrected GCM inputs yield very good agreement with the observation-based inputs in average magnitude of runoff and streamflow. On global average, the observation-based simulated mean runoff and streamflow both decreased about 1.3% from 1971 to 2001. However, GCM-based simulations yield increasing trends over …


Estimating The Probability Of Vegetation To Be Groundwater Dependent Based On The Evaluation Of Tree Models, Isabel C. Pérez Hoyos, Nir Y. Krakauer, Reza Khanbilvardi Apr 2016

Estimating The Probability Of Vegetation To Be Groundwater Dependent Based On The Evaluation Of Tree Models, Isabel C. Pérez Hoyos, Nir Y. Krakauer, Reza Khanbilvardi

Publications and Research

Groundwater Dependent Ecosystems (GDEs) are increasingly threatened by humans’ rising demand for water resources. Consequently, it is imperative to identify the location of GDEs to protect them. This paper develops a methodology to identify the probability of an ecosystem to be groundwater dependent. Probabilities are obtained by modeling the relationship between the known locations of GDEs and factors influencing groundwater dependence, namely water table depth and climatic aridity index. Probabilities are derived for the state of Nevada, USA, using modeled water table depth and aridity index values obtained from the Global Aridity database. The model selected results from the performance …


Ensemble Forecasts: Probabilistic Seasonal Forecasts Based On A Model Ensemble, Hannah Aizenman, Michael D. Grossberg, Nir Y. Krakauer, Irina Gladkova Mar 2016

Ensemble Forecasts: Probabilistic Seasonal Forecasts Based On A Model Ensemble, Hannah Aizenman, Michael D. Grossberg, Nir Y. Krakauer, Irina Gladkova

Publications and Research

Ensembles of general circulation model (GCM) integrations yield predictions for meteorological conditions in future months. Such predictions have implicit uncertainty resulting from model structure, parameter uncertainty, and fundamental randomness in the physical system. In this work, we build probabilistic models for long-term forecasts that include the GCM ensemble values as inputs but incorporate statistical correction of GCM biases and different treatments of uncertainty. Specifically, we present, and evaluate against observations, several versions of a probabilistic forecast for gridded air temperature 1 month ahead based on ensemble members of the National Centers for Environmental Prediction (NCEP) Climate Forecast System Version 2 …


A Review Of Advances In The Identification And Characterization Of Groundwater Dependent Ecosystems Using Geospatial Technologies, Isabel C. Pérez Hoyos, Nir Y. Krakauer, Reza Khanbilvardi, Roy A. Armstrong Mar 2016

A Review Of Advances In The Identification And Characterization Of Groundwater Dependent Ecosystems Using Geospatial Technologies, Isabel C. Pérez Hoyos, Nir Y. Krakauer, Reza Khanbilvardi, Roy A. Armstrong

Publications and Research

Groundwater Dependent Ecosystem (GDE) protection is increasingly being recognized as essential for the sustainable management and allocation of water resources. GDE services are crucial for human well-being and for a variety of flora and fauna. However, the conservation of GDEs is only possible if knowledge about their location and extent is available. Several studies have focused on the identification of GDEs at specific locations using ground-based measurements. However, recent progress in remote sensing technologies and their integration with Geographic Information Systems (GIS) has provided alternative ways to map GDEs at a much larger spatial extent. This paper presents a review …


Sefo: A Package For Generating Probabilistic Forecasts From Nmme Predictive Ensembles, Nir Krakauer Mar 2016

Sefo: A Package For Generating Probabilistic Forecasts From Nmme Predictive Ensembles, Nir Krakauer

Publications and Research

Long-range weather forecasts based on output from ensembles of computer simulations are attracting increasing interest. A variety of methods have been proposed to convert the ensemble outputs to calibrated probabilistic forecasts. The package presented here (SeFo, for Seasonal Forecasting) implements a number of methods for producing forecasts of monthly surface air temperature anomalies up to 9 months in advance using output from the North American Multi-Model Ensemble (NMME). The package contains modules for downloading and reading past observations and ensemble output; producing forecast probability distributions; and verifying and calibrating a user-determined subset of methods using arbitrary past periods. By changing …


Evaluation Of Viirs Land Surface Temperature Using Crest-Safe Air, Snow Surface, And Soil Temperature Data, Carlos L. Pérez Díaz, Tarendra Lakhankar, Peter Romanov, Reza Khanbilvardi, Yunyue Yu Dec 2015

Evaluation Of Viirs Land Surface Temperature Using Crest-Safe Air, Snow Surface, And Soil Temperature Data, Carlos L. Pérez Díaz, Tarendra Lakhankar, Peter Romanov, Reza Khanbilvardi, Yunyue Yu

Publications and Research

In this study, the Visible Infrared Imager Radiometer Suite (VIIRS) Land Surface Temperature (LST) Environmental Data Record (EDR) was evaluated against snow surface (T-skin) and near-surface air temperature (T-air) ground observations recorded at the Cooperative Remote Sensing Science and Technology Center—Snow Analysis and Field Experiment (CREST-SAFE), located in Caribou, ME, USA during the winters of 2013 and 2014. The satellite LST corroboration of snow-covered areas is imperative because high-latitude regions are often physically inaccessible and there is a need to complement the data from the existing meteorological station networks. T-skin is not a standard meteorological parameter commonly observed at synoptic …


Evaluation Of The Snow Thermal Model (Sntherm) Through Continuous In Situ Observations Of Snow’S Physical Properties At The Crest-Safe Field Experiment, José Alberto Infante Corona, Jonathan Muñoz, Tarendra Lakhankar, Peter Romanov, Reza Khanbilvardi Nov 2015

Evaluation Of The Snow Thermal Model (Sntherm) Through Continuous In Situ Observations Of Snow’S Physical Properties At The Crest-Safe Field Experiment, José Alberto Infante Corona, Jonathan Muñoz, Tarendra Lakhankar, Peter Romanov, Reza Khanbilvardi

Publications and Research

Snowpack properties like temperature or density are the result of a complex energy and mass balance process in the snowpack that varies temporally and spatially. The Snow Thermal Model (SNTHERM) is a 1-dimensional model, energy and mass balance-driven, that simulates these properties. This article analyzes the simulated snowpack properties using SNTHERM forced with two datasets, namely measured meteorological data at the Cooperative Remote Sensing Science and Technology-Snow Analysis and Field Experiment (CREST-SAFE) site and the National Land Data Assimilation System (NLDAS). The study area is located on the premises of Caribou Municipal Airport at Caribou (ME, USA). The model evaluation …


Probabilistic Precipitation Estimation With A Satellite Product, Nir Y. Krakauer, Soni M. Pradhanang, Jeeban Panthi, Tarendra Lakhankar, Ajay K. Jha Apr 2015

Probabilistic Precipitation Estimation With A Satellite Product, Nir Y. Krakauer, Soni M. Pradhanang, Jeeban Panthi, Tarendra Lakhankar, Ajay K. Jha

Publications and Research

Satellite-based precipitation products have been shown to represent precipitation well over Nepal at monthly resolution, compared to ground-based stations. Here, we extend our analysis to the daily and subdaily timescales, which are relevant for mapping the hazards caused by storms as well as drought. We compared the Tropical Rainfall Measuring Mission (TRMM) Multi-satellite Precipitation Analysis (TMPA) 3B42RT product with individual stations and with the gridded APHRODITE product to evaluate its ability to retrieve different precipitation intensities. We find that 3B42RT, which is freely available in near real time, has reasonable correspondence with ground-based precipitation products on a daily timescale; rank …


Spatial And Temporal Variability Of Rainfall In The Gandaki River Basin Of Nepal Himalaya, Jeeban Panthi, Piyush Dahal, Madan Lall Shrestha, Suman Aryal, Nir Y. Krakauer, Soni M. Pradhanang, Tarendra Lakhankar, Ajay K. Jha, Mohan Sharma, Ramchandra Karki Mar 2015

Spatial And Temporal Variability Of Rainfall In The Gandaki River Basin Of Nepal Himalaya, Jeeban Panthi, Piyush Dahal, Madan Lall Shrestha, Suman Aryal, Nir Y. Krakauer, Soni M. Pradhanang, Tarendra Lakhankar, Ajay K. Jha, Mohan Sharma, Ramchandra Karki

Publications and Research

Landslides, floods, and droughts are recurring natural disasters in Nepal related to too much or too little water. The summer monsoon contributes more than 80% of annual rainfall, and rainfall spatial and inter-annual variation is very high. The Gandaki River, one of the three major rivers of Nepal and one of the major tributaries of the Ganges River, covers all agro-ecological zones in the central part of Nepal. Time series tests were applied for different agro-ecological zones of the Gandaki River Basin (GRB) for rainfall trends of four seasons (pre-monsoon, monsoon, post-monsoon and winter) from 1981 to 2012. The non-parametric …


Economic Growth Assumptions In Climate And Energy Policy, Nir Y. Krakauer Mar 2014

Economic Growth Assumptions In Climate And Energy Policy, Nir Y. Krakauer

Publications and Research

The assumption that the economic growth seen in recent decades will continue has dominated the discussion of future greenhouse gas emissions and the mitigation of and adaptation to climate change. Given that long-term economic growth is uncertain, the impacts of a wide range of growth trajectories should be considered. In particular, slower economic growth would imply that future generations will be relatively less able to invest in emissions controls or adapt to the detrimental impacts of climate change. Taking into consideration the possibility of economic slowdown therefore heightens the urgency of reducing greenhouse gas emissions now by moving to renewable …


Assessing The Performance Of A Northern Gulf Of Mexico Tidal Model Using Satellite Imagery, Stephen C. Medeiros, Scott C. Hagen, Naira Chaouch, Jesse Feyen, Marouane Temimi, John F. Weishampel, Yuji Funakoshi, Reza Khanbilvardi Nov 2013

Assessing The Performance Of A Northern Gulf Of Mexico Tidal Model Using Satellite Imagery, Stephen C. Medeiros, Scott C. Hagen, Naira Chaouch, Jesse Feyen, Marouane Temimi, John F. Weishampel, Yuji Funakoshi, Reza Khanbilvardi

Publications and Research

Tidal harmonic analysis simulations along with simulations spanning four specific historical time periods in 2003 and 2004 were conducted to test the performance of a northern Gulf of Mexico tidal model. A recently developed method for detecting inundated areas based on integrated remotely sensed data (i.e., Radarsat-1, aerial imagery, LiDAR, Landsat 7 ETM+) was applied to assess the performance of the tidal model. The analysis demonstrates the applicability of the method and its agreement with traditional performance assessment techniques such as harmonic resynthesis and water level time series analysis. Based on the flooded/non-flooded coastal areas estimated by the integrated remotely …


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 Jul 2012

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 Apr 2012

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 …


Dissemination Of Geological Information In Avoiding Geotechnical Risks Associated With Tunnel Construction: Lessons Learned From Deep Voids In Marble In Lower Manhattan, New York City, Nazrul I. Khandaker, Stanley Schleifer, Masud Ahmed, Leah Scott Oct 2011

Dissemination Of Geological Information In Avoiding Geotechnical Risks Associated With Tunnel Construction: Lessons Learned From Deep Voids In Marble In Lower Manhattan, New York City, Nazrul I. Khandaker, Stanley Schleifer, Masud Ahmed, Leah Scott

Publications and Research

Test boring associated with the recently accomplished City Water Tunnel # 3 in Manhattan, New York City revealed moderately to highly weathered marble with insoluble silicate residues composed mostly of phlogopite, chlorite, and tremolite. Apparent control on the weatherability of the marble was in response to original mineral constituents dominating this lithology. Encountered marble samples ranged between pure calcitic to mixed dolomitic/siliceous types. Fresh marble samples collected from adjacent boring locations revealed characteristic geochemical data: Lime (25-45%), Silica (4-7%), Alumina (1-3%), MgO (5-20%), and LOI (35-42%); compressive strength of unweathered marble varied between 2000-3000 Kg/cm2. Relict foliations with …