A5017870222- Astro and Planetary Science
- Planetary Science and Exploration
- Isotope Analysis in Ecology
- Geophysics and Gravity Measurements
- Geology and Paleoclimatology Research
- Solar and Space Plasma Dynamics
- Hydrology and Watershed Management Studies
- Space Exploration and Technology
- Geological formations and processes
- Groundwater and Isotope Geochemistry
- Geochemistry and Geologic Mapping
- Synthetic Aperture Radar (SAR) Applications and Techniques
- Flood Risk Assessment and Management
- Geological and Geochemical Analysis
- Groundwater and Watershed Analysis
- earthquake and tectonic studies
- Marine and coastal ecosystems
- Space Science and Extraterrestrial Life
- Soil and Water Nutrient Dynamics
- Soil erosion and sediment transport
- Climate variability and models
- Remote Sensing and LiDAR Applications
- Scientific Research and Discoveries
- Groundwater flow and contamination studies
- Aeolian processes and effects
University of Toledo
2013-2023
University of Dundee
2018
NYU Langone Health
2018
University of Minnesota
1994-2017
Twin Cities Orthopedics
2017
Western Michigan University
2007-2009
University at Buffalo, State University of New York
2004
Argonne National Laboratory
1999
University of Minnesota System
1986-1993
Washington University in St. Louis
1993
Measurements of 81Kr/Kr in deep groundwater from the Nubian Aquifer (Egypt) were performed by a new laser-based atom-counting method. 81Kr ages range \~2x10^5 to ~1x10^6 yr, correlate with 36Cl/Cl ratios, and are consistent lateral flow recharge area near Uweinat Uplift SW Egypt. Low delta-2H values 81Kr-dated reveal recurrent Atlantic moisture source during Pleistocene pluvial periods. These results indicate that method for dating old is robust such measurements can now be applied wide...
Climate change has led to more frequent extreme winters (aka, dzud) and summer droughts on the Mongolian Plateau during last decade. Among these events, 2000–2002 combined drought–dzud 2010 dzud were most severe vegetation. We examined vegetation response extremes through past decade across as compared decadal means. first assessed severity extent of drought using Tropical Rainfall Measuring Mission (TRMM) precipitation data Palmer index (PDSI). then effects by mapping anomalies in indices...
Harmful algal blooms (HABs) in the Western Basin (WB) of Lake Erie have been linked to nonpoint pollution from agricultural watersheds. The Maumee River watershed is largest Great Lakes region and delivers biggest sediment nutrient load Erie. Climate change could alter magnitude timing delivery Erie's WB. Data four Coupled Model Intercomparison Project Phase 5 (CMIP5) models were inputted into a calibrated Soil Water Assessment Tool (SWAT) model determine effects climate on yields. Tillage...
Abstract Net ecosystem carbon dioxide (F CO2 ) and methane CH4 exchanges were measured by using the eddy covariance method to quantify atmospheric budget at a Typha ‐ Nymphaea ‐dominated freshwater marsh (March 2011 March 2013) soybean cropland (May May 2012) in northwestern Ohio, USA. Two year average annual F (49.7 g C‐CH 4 m −2 yr −1 from was high compatible with its net CO 2 uptake : −21.0 C‐CO ). In contrast, small (2.3 accounted for minor portion of −151.8 cropland. At seasonal scale,...
The Nile Delta formed by progression of a complex system deltaic fans throughout the Pleistocene, with Modern delta being from sediments supplied at least ten distinct distributaries Holocene. With an average elevation approximately 1 m above sea level within 30 km coast and predicted rise in 1.8—5.9 mm/yr subsidence northern has become topic major concern to Egyptian population government. is home more than 50 million people agricultural production area for Egypt. We evaluated modern rates...
[1] The Sample Analysis at Mars (SAM) instrument suite on the Science Laboratory (MSL) measured a atmospheric14N/15N ratio of 173 ± 11 sol 341 mission, agreeing with Viking's measurement 168 17. MSL/SAM value was based Quadrupole Mass Spectrometer measurements an enriched atmospheric sample, CO2 and H2O removed. Doubly ionized nitrogen data m/z 14 14.5 had highest signal/background ratio, results confirmed by 28 29 data. Gases in SNC meteorite glasses have been interpreted as mixtures...
Abstract Persistent scatterer interferometric analyses were conducted on a stack of 84 Environmental Satellite's Advanced Synthetic Aperture Radar scenes spanning 7 years (2004 to 2010) over the entire Nile Delta Egypt and surroundings (area: 40,416 km 2 ) monitor ongoing spatial temporal land deformation, identify factors controlling model interplay between sea level rise subsidence areas populations threatened by encroachment end 21st century. Findings include following: (1) general...
Abstract To understand the carbon and energy exchange between lake surface atmosphere, direct measurements of latent, sensible heat, CO 2 fluxes were taken using eddy covariance (EC) technique in Western Lake Erie during October 2011 to September 2013. We found that latent heat flux ( LE ) had a marked one‐peak seasonal change both years differed from diurnal course lacked sinusoidal dynamic common terrestrial ecosystems. Daily mean was 4.8 ± 0.1 4.3 0.2 MJ m −2 d −1 Year 1 2, respectively....
Water quality issues continue to impact recreational and resource use of waterways in the Great Lakes across smaller inland water bodies their watersheds. With advancements small unmanned aerial systems (sUAS) sensor production, sUAS offer flexibility overcome several shortcomings satellite airborne systems, complement measurements this environment. In study, we deployed two different low-cost, boat launchable configurations instrumented with Ocean Optics STS hyperspectral Vis-NIR...
Research Article| May 01, 2011 Integration of GRACE (Gravity Recovery and Climate Experiment) data with traditional sets for a better understanding the time-dependent water partitioning in African watersheds Mohamed Ahmed; Ahmed 1Department Geosciences, Western Michigan University, 1903 West Avenue, Kalamazoo, 49008, USA Search other works by this author on: GSW Google Scholar Sultan; Sultan John Wahr; Wahr 2Department Physics, University Colorado at Boulder, 2000 80309, Eugene Yan; Yan...