Article
Meteorology & Atmospheric Sciences
Siyu Zhao, Rong Fu, Michael L. Anderson, Sudip Chakraborty, Jonathan H. Jiang, Hui Su, Yu Gu
Summary: This study provides extended seasonal predictions for UCRB spring precipitation using an ANN model and a linear regression model. The study finds that the extratropical North Pacific has a higher correlation with UCRB spring precipitation. The prediction models have high correlation coefficients (>0.45), low errors (<20%), and good skill scores (>50%).
Article
Meteorology & Atmospheric Sciences
Heechan H. An, Tadesse A. Abitew, Seonggyu Park, Colleen H. M. Green, Jaehak Jeong
Summary: This study evaluated the reliability of gridded precipitation products from satellite-based systems in the western United States and found that the accuracy of precipitation estimates is affected by topographical conditions, seasonality, and location.
JOURNAL OF HYDROMETEOROLOGY
(2023)
Article
Environmental Sciences
Cynthia L. Norton, Matthew P. Dannenberg, Dong Yan, Cynthia S. A. Wallace, Jesus R. Rodriguez, Seth M. Munson, Willem J. D. van Leeuwen, William K. Smith
Summary: The study focused on estimating fallow and active cropland extent in different CRB agricultural regions at a high spatial resolution. Factors such as climate, water rights, and market value were found to influence irrigation water demands and cropland productivity differently in various regions.
Article
Engineering, Environmental
David W. Pierce, Daniel R. Cayan, Jordan Goodrich, Tapash Das, Armin Munevar
Summary: The study evaluates three generations of global climate models (GCMs) in simulating seasonal mean and variability of temperature and precipitation in the Upper Colorado River Basin, with a focus on low-frequency precipitation variability associated with drought. The evaluation also includes the study of remote teleconnected atmospheric responses to the Pacific Ocean.
JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION
(2022)
Article
Astronomy & Astrophysics
Carl J. Talsma, Katrina E. Bennett, Velimir V. Vesselinov
Summary: This study uses climate simulations to predict drought indicators in the Colorado River Basin (CRB) and applies an unsupervised machine learning approach to analyze the results. The findings suggest that the CRB will face increasing water scarcity and evaporative demand under climate change. Significant changes in peak runoff are observed in snowmelt-dominant sub-watersheds, with some sub-watersheds experiencing the complete disappearance of the snowmelt signal. This research demonstrates the utility of the unsupervised ML approach in analyzing hydro climate model results and understanding the potential impacts of drought.
EARTH AND SPACE SCIENCE
(2022)
Article
Engineering, Civil
Ximeng Xu, Xiaobo Yun, Qiuhong Tang, Huijuan Cui, Jie Wang, Lu Zhang, Deliang Chen
Summary: Climate change is expected to increase rainfall erosivity over the Lancang-Mekong River Basin, especially under high emission scenarios. Summer rainfall erosivity in June to August is projected to account for the majority of annual rainfall erosivity. These changes can provide insights into the risk of soil erosion under climate change in the region.
JOURNAL OF HYDROLOGY
(2023)
Article
Ecology
Shouming Feng, Zhenke Zhang, Shuhe Zhao, Xinya Guo, Wanyi Zhu, Priyanko Das
Summary: The study analyzed the variation of NDVI in the Mara River Basin in East Africa and identified a time lag in the vegetation's response to seasonal variation. The results showed that NDVI increased in 75% of the basin areas, with a decreasing trend in 3.5% of areas, mainly savannas. The dominant time lag effect was one month, but there were spatial and temporal disparities. The average time lag based on the distribution of NDVI characteristic peaks was 35.5 days and increased with the range of seasons.
ECOLOGICAL PROCESSES
(2023)
Article
Geosciences, Multidisciplinary
Mu Xiao, Dennis P. Lettenmaier
Summary: The study utilized a macroscale hydrology model and an atmospheric river catalog to evaluate snow accumulation in the Upper Colorado River basin affected by atmospheric rivers. It was found that most atmospheric rivers affecting UCRB first pass through the Sierra Nevada region, resulting in greater snow accumulation there.
GEOPHYSICAL RESEARCH LETTERS
(2021)
Article
Engineering, Environmental
Muhammad Mohsin, Juergen Pilz
Summary: Extreme weather changes globally lead to disasters like droughts. Developing probability models and long-term planning can reduce the detrimental effects of droughts. A new model for predicting interarrival times of droughts is proposed in this paper based on Bivariate Affine-Linear Exponential distribution, with reliable forecasting and estimation of return periods for future planning.
STOCHASTIC ENVIRONMENTAL RESEARCH AND RISK ASSESSMENT
(2021)
Article
Engineering, Environmental
Homa Salehabadi, David G. Tarboton, Bradley Udall, Kevin G. Wheeler, John C. Schmidt
Summary: Since 1995, much has been learned about Colorado River hydrology. By analyzing historical flows, tree-ring reconstructions, and climate change, researchers have gained a better understanding of future drought conditions. The study shows that even more severe droughts are possible, based on tree-ring reconstructed flows and future flows projected from climate models. This has significant implications for the management and operation of reservoirs in the Colorado River Basin.
JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION
(2022)
Article
Geosciences, Multidisciplinary
Subhrendu Gangopadhyay, Connie A. Woodhouse, Gregory J. McCabe, Cody C. Routson, David M. Meko
Summary: The ongoing drought in the Upper Colorado River Basin has been found to be extremely severe, especially when compared to the tree-ring records from as early as 762 CE. Using gridded drought-atlas data and streamflow data, researchers have developed a streamflow reconstruction model for the Lees Ferry gage, revealing a second-century drought that surpasses the severity of the current drought and documented medieval period droughts. Limited data also support the occurrence of this exceptional second-century drought through analysis of individual tree-ring records and other paleoclimatic data.
GEOPHYSICAL RESEARCH LETTERS
(2022)
Article
Water Resources
V Dos Santos, R. A. Juca Oliveira, P. Datok, S. Sauvage, A. Paris, M. Gosset, J. M. Sanchez-Perez
Summary: This study compares different satellite-based precipitation products for a hydrological model in the Congo River Basin. The findings show that satellite-only products tend to overestimate rainfall season peaks, while products that consider gauge calibration exhibit better agreement. The hydrological model is able to reproduce precipitation characteristics, with gauge-adjusted satellite products performing better than those without adjustment.
JOURNAL OF HYDROLOGY-REGIONAL STUDIES
(2022)
Article
Astronomy & Astrophysics
Yun Lin, Yoshihide Takano, Yu Gu, Jingyu Wang, Bin Zhao, Kuo-Nan Liou, Rong Fu
Summary: The study found that in the upper Colorado River basin, the annual trend of runoff in March is more statistically significant than in other months. The decrease in cloud optical depth may lead to reduced precipitation and increased temperature in March, resulting in a reduction of available water resources.
EARTH AND SPACE SCIENCE
(2022)
Article
Biodiversity Conservation
Lise Comte, Julian D. Olden, Stacy Lischka, Brett G. Dickson
Summary: Freshwater ecosystems are facing a severe biodiversity crisis, and it is crucial to develop reliable indicators to assess ecological integrity and identify specific threats and pathways of impairment. In this study, the Colorado River Basin is used as a case study to assess the ecological integrity of riverine ecosystems using a spatial framework that considers various human activities, pathways, and extent of influence. The study quantifies and maps threat indices for different stream segments and identifies disparities in terms of overall degree of threat and priorities for different parts of the Basin. The results demonstrate the potential of multi-faceted threat mapping in informing spatial planning decision processes and assessing ecological integrity in the absence of extensive in situ measurements.
ECOLOGICAL INDICATORS
(2022)
Article
Environmental Sciences
Jeongwoo Hwang, Hemant Kumar, Albert Ruhi, Arumugam Sankarasubramanian, Naresh Devineni
Summary: Dams have a significant impact on the frequencies of natural streamflow in highly regulated river networks, leading to changes in river flow regimes with varying trends along different sections of the river.
WATER RESOURCES RESEARCH
(2021)
Article
Environmental Sciences
Binita Shrestha, Sajjad Ahmad, Haroon Stephen
Summary: Urbanization leads to the development of impervious surfaces in open spaces and agricultural fields, affecting natural water infiltration and causing flooding and water pollution. This study utilizes satellite data and classifiers to assess impervious surface growth trends in Lahore from 2015 to 2021, aiming to develop a reliable mapping method for environmental management in the city.
ENVIRONMENTAL MONITORING AND ASSESSMENT
(2021)
Article
Environmental Sciences
Binita Shrestha, Haroon Stephen, Sajjad Ahmad
Summary: This study successfully mapped impervious surfaces of nine Pakistani cities and estimated their growth rates using a fusion technique with Sentinel 1 and 2 satellite data. The approach achieved high accuracy of 98% and strong linear relationship with external data. The findings provide valuable information for urban planners and environmentalists.
Article
Green & Sustainable Science & Technology
Usha Poudel, Haroon Stephen, Sajjad Ahmad
Summary: This study evaluated irrigation equity, adequacy, and crop water productivity for alfalfa and sugar beet in Southern California's Imperial Valley. Results showed high irrigation adequacy but significant room for improvement in crop water productivity. The study's findings could help water managers target fields for water conservation and management efforts.
Article
Environmental Sciences
Rubab Saher, Haroon Stephen, Sajjad Ahmad
Summary: Urban landscapes, characterized by unique buildings, pavements, and vegetation, have complex effects on the atmosphere. Research shows that canyons are the major cause of daytime cooling and nighttime warming. Different surface types have different cooling effects, for example, turfgrass is 4°C cooler than canyons, and north-south oriented canyons are 2°C cooler than east-west oriented canyons.
Article
Environmental Sciences
Rubab Saher, Haroon Stephen, Sajjad Ahmad
Summary: This study examines the effects of land use change in the arid Las Vegas Valley on surface characteristics, finding that urbanization significantly affects surface temperature and evapotranspiration. Urban surfaces, such as commercial buildings and roadways, have been identified as key contributors to increased land surface temperature.
Article
Computer Science, Interdisciplinary Applications
Amrit Bhusal, Ajay Kalra, Sangmin Shin
Summary: This study investigates the resilience effects of decentralized detention systems on extreme flooding events in urban areas. It proposes an integrated flood resilience measure and identifies the best locations for distributed detention ponds. The findings suggest the importance of incorporating decentralization strategies into decision-making to cope with extreme flooding events in urban watersheds.
JOURNAL OF HYDROINFORMATICS
(2023)
Review
Environmental Sciences
Godson Ebenezer Adjovu, Haroon Stephen, David James, Sajjad Ahmad
Summary: This study provides an overview of the techniques, shortcomings, and strengths of remote sensing (RS) applications in the retrieval and monitoring of water quality parameters (WQPs) such as chlorophyll-a concentration, turbidity, total suspended solids, colored dissolved organic matter, total dissolved solids. RS applications offer effective quantification and monitoring of WQPs on a spatiotemporal scale. Various algorithms, including empirical, analytical, semi-empirical, and machine-learning, have been used for water quality monitoring using RS. Optical and microwave sensors have been applied for the estimation of WQPs, with optical RS further classified as spaceborne and airborne sensors based on their platform.
Article
Environmental Sciences
Fereshteh Kolahdouzan, Hossein Afzalimehr, Seyed Mostafa Siadatmousavi, Asal Jourabloo, Sajjad Ahmad
Summary: This experimental study investigates the effect of horizontal pipeline arrangement changes on velocity pattern and scouring process. Four cases were examined: single pipe, two pipes with distances of 0.5 D and D, and three pipes with a distance of 0.5 D (D being the pipe diameter). The upstream, downstream, and on-pipe velocities were measured using an Acoustic Doppler Velocimeter (ADV). Results showed that the scouring depth was highest for the single pipe case and decreased significantly (by 28.6%) with the presence of a second pipe at a distance of 0.5 D. Increasing the number of pipes to three at a distance of 0.5 D further reduced the scouring depth by 47.6% compared to the single pipe case. However, in the case of two pipes at a distance of D, the reduction in scouring depth was 21.4% compared to the single pipe case and increased by 10% compared to the two pipes at 0.5 D distance case.
Article
Green & Sustainable Science & Technology
Sanaz Hadian, Hossein Afzalimehr, Sajjad Ahmad
Summary: Changes in channel or river width have significant impacts on river engineering and flow resistance. Studying the effect of width changes on flow structures helps control erosion and sedimentation in coarse-bed rivers and improve ecological restoration projects' design. The study investigated the effect of sequential pool-riffle and bank narrowness on turbulent flow characteristics through experimental research in variable and fixed width flumes. The findings showed that the flow depth increase expanded negative and low longitudinal velocities, and entering the middle part of the pool reduced the flow width. The maximum turbulence intensity and Reynolds shear stress were higher in variable width mode compared to fixed width mode. Understanding flow patterns and velocity distribution in variable width streams enhances engineers' ability to estimate controlling parameters in river restoration and improve hydraulic models' performance.
Article
Environmental Sciences
Amrit Bhusal, Amrit Babu Ghimire, Balbhadra Thakur, Ajay Kalra
Summary: Flooding events have significant impacts on populations worldwide. Due to climate change and urbanization, the severity and frequency of extreme flooding events are increasing. Accurate hydrologic modelling is crucial for flood control systems. Precipitation data plays a vital role in developing hydrologic models. Traditional point gauge observations have limitations in capturing the temporal and spatial variability of precipitation. Radar-based precipitation products, such as NEXRAD III, have been used as an alternative. This study evaluates the performance of NEXRAD III for hydrologic analysis and highlights its superiority in generating discharge hydrographs compared to gauge station data.
MODELING EARTH SYSTEMS AND ENVIRONMENT
(2023)
Article
Water Resources
Godson Ebenezer Adjovu, Haroon Stephen, Sajjad Ahmad
Summary: The Colorado River, a crucial water source for millions of people and farmlands in the western US and Mexico, is facing elevated total dissolved solid (TDS) and total suspended solid (TSS) concentrations. This study analyzed the spatiotemporal variability in TDS and TSS concentrations and found significant differences in these parameters between the upper and lower basins of the river. The findings help understand water quality, detect sources of pollution, and guide legislative actions.
Article
Multidisciplinary Sciences
Swarupa Paudel, Neekita Joshi, Ajay Kalra
Summary: Climate change is a major global challenge that has led to changes in hydrological extremes. This study evaluates the flooding patterns and extent of two different rivers using observed data and climate models. The findings indicate a rapid increase in flooding events, even in small creeks, in the upcoming years. The study aims to assist floodplain managers in strategic planning and provide sustainable strategies for floodplain management in similar regions.
Article
Multidisciplinary Sciences
Abhiru Aryal, Albira Acharya, Ajay Kalra
Summary: Climate change has caused uncertainty in hydrological patterns, leading to various natural disasters. This research study aims to examine the impact of climate change on flooding patterns by comparing historical and future simulated scenarios, and provide necessary background for emergency response plans.
Article
Water Resources
Amrit Bhusal, Utsav Parajuli, Sushmita Regmi, Ajay Kalra
Summary: This research compares the effectiveness of the machine learning model Random Forest with the conventional process-based model HEC-HMS in rainfall-runoff simulation. The statistical index values demonstrate the good performance of both the Random Forest and HEC-HMS models in hydrology analysis. Additionally, the Random Forest model underestimates the flood depth during peak flooding events, while HEC-HMS can compensate for this discrepancy.
Article
Water Resources
Rubab Saher, Ariane Middel, Haroon Stephen, Sajjad Ahmad
Summary: This study investigated the microclimate effects and irrigation water requirements of three landscape types in an arid region of Phoenix, AZ. The results show that the mesic landscape induced cooling effects, but had high water consumption. The oasis landscape had stronger daytime cooling but comparable nighttime warming to the xeric landscape.
