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Full-Text Articles in Engineering

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 …


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 …


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 …


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 …


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 …


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 …


Tunnel Geology As Seen By Geologists: Manhattan, New York City, Nazrul I. Khandaker, Stanley Schleifer, Masud Ahmed, Alan R. Slaughter, Belal A. Sayeed, Dorean J. Flores, Mario Jo-Ramirez Oct 2005

Tunnel Geology As Seen By Geologists: Manhattan, New York City, Nazrul I. Khandaker, Stanley Schleifer, Masud Ahmed, Alan R. Slaughter, Belal A. Sayeed, Dorean J. Flores, Mario Jo-Ramirez

Publications and Research

Current exploratory boring operations in and around Manhattan, New York City are providing geologists and geotechnical engineers with a plethora of new and interesting geological information, which has not been previously reported. The rocks encountered, mostly medium to high-grade metamorphic rocks, with both mafic and felsic intrusives, are highly variable in competency and mechanical durability. One of the most frequently encountered rock types is a garnetiferous-muscovite-biotite schist which grades into schistose gneiss and displays a wide variety of structural, compositional, and textural attributes. Metamorphic minerals showing the variable degree of metamorphism include graphite, talc, garnet, kyanite, tourmaline, emory, and occasionally …