Data Server with UC San Diego / San Diego Super Computer Center
The UC Center for Hydrologic Modeling (UCCHM) is partnering with the San Diego Super Computer Center (SDSC) and the Consortium of Universities for the Advancement of Hydrologic Science, Inc. (CUAHSI) to build a state-of-the-art, integrated computer model and data products for the state of California. The goal is to inform and advise state, regional, national and international leaders of our findings, projections and the future of water availability. Ultimately, it will be accessible to a broader group of stakeholders including local, state and federal agencies and academic and non-profit research groups. The hydrology-specific infrastructure will support integration of multiple datasets from distributed information sources, converting them into formats suitable for modeling and visualization needs. Also, it provides standardized methodology to access data in various formats and to link with models which have different interfaces.
The system will use unified services and interfaces with a goal towards compatibility with HIS infrastructure, CHyMP, CSDMS, LIS/ESMF and/or OpenMI model processing. The data services, model services, and other processing services will be registered in a UCCHM catalog to enable data discovery and data delivery to applications. CUAHSI ODM is the data model for storing observational data, and HIS server components to publish water observations data services; THREDDS for gridded data; GeoServer for spatial data. IRODS storage infrastructure is exploited to store and replicate large volumes of data, enable fast data exchange between UCCHM nodes and seamless extension of storage capacity when required by modeling needs. To the degree possible we will develop UCCHM models as regional prototypes for CHyMP, and Model processing services will take advantage of existing UCI and UCSD high performance computing resources.
Understanding factors that control outdoor residential water use
Outdoor water use applied to landscapes has become of concern in water-stressed areas such as Orange County, where it can more than double household water use. We are conducting a study in partnership with the Municipal Water District of Orange County (MWDOC) to understand the biophysical and socioeconomic variables that influence outdoor water use in Orange County. We are analyzing the effects of climate (humidity, temperature, precipitation, drought), lot characteristics (lot size, presence of a pool, management practice, vegetation type), and socioeconomic factors (income, size of household, ethnicity) on outdoor water use. Ultimately, the goal of this research is to couple a spatially-distributed integrated water balance model with biophysical and socioeconomic drivers to simulate urban outdoor water demand. This research will inform policies to promote more efficient and equitable water use. Results could help in the development of practices to conserve water in response to water scarcity predicted as a result of climate change and population growth.
Irrigation in California’s Central Valley Strengthens the North American Monsoon
Agricultural irrigation in the California's Central Valley has always depended on surface water reservoirs and groundwater pumping. This anthropogenic redistribution of water modifies the land hydrological cycle significantly, especially by increasing evapotranspiration. We use the global, NCAR Community Atmosphere Model, with realistic estimates of irrigation applied to the NCAR Community Land Model. Simulation results show that irrigation modifies the surface radiation budget by generally increasing latent heat, decreasing sensible heat and decreasing land surface temperature. Although atmospheric water vapor increases due to enhanced evapotranspiration, during the summer, the Central Valley underlies the descending branch of the large-scale circulation, which inhibits the occurrence of convection. Consequently, Central Valley irrigation has negligible effects on local precipitation. However, precipitation in the downwind region of California, i.e., in the southwestern United States, increases, enhancing the North American Monsoon, while forming a regional, anthropogenic recycling loop in the hydrologic cycle which returns water to California. This study has implications for the importance of human-driven impacts on the hydrological cycle and local and regional climate, and for water resources management in California and the Western United States.
Snowload Estimation using GRACE and GPS
Accurate estimation of the winter snowpack is crucial for prediction of available water supply, flooding, and climate feedbacks. Remote sensing of snow is currently limited to observations of the spatial extent of the snowpack. GPS observations of vertical land surface loading reveal seasonal responses of the land surface to the total weight of snow, providing information about the stored snow water equivalent. The seasonal signal in SOPAC GPS vertical land surface position time series is shown to be dominated by direct elastic loading of the crust by the snowpack and soil moisture in 4 locations in the Western United States. GPS observations of land surface deformation are then used to predict the water equivalent load as a function of time and compared to Snotel observations.
Managed water balance of California
California’s water resources have been in steady decline over the past seven years and at a high priority to local hydrologists, farmers and politicians. The Central Valley is the greatest producer of food in the United States and if farmers do not receive their water allocations, the entire nation will be affected. Hydrologists have used the Gravity Recovery and Climate Experiment (GRACE) to calculate a natural water balance for the Sacramento-San Joaquin River Basin, the main basin running north to south in California. Since 2005, there have been major implications of drought in the Central Valley with a steep decline in groundwater seen by the dual-satellite GRACE mission. However, since California is one of the most heavily water-managed states in the world, it is important to recognize the managed water balance to better understand where water is flowing, who is receiving water allocations and what the water is being used for. In our research, we propose to quantify the amount of water being diverting to the Central Valley via the Central Valley Project (CVP) as well as the water diverted to Southern California via the State Water Project (SWP) through the complex series of piping and pumping plants that serve as the basis for each project. We will also looks at the amount of Colorado River water being diverted to the Metropolitan Water District (MWD) in Southern California. We will quantify these amounts and determine how much water counties are using and determine the water use by working with individual water districts.
Quantifying Water Storage Changes in the Colorado River Basin
Southern California's water supply is in a fragile state as its largest source of imported water, the Colorado River, is diminishing in response to climate change and overuse by growing populations. The UCCHM Colorado River Basin project uses satellite data to monitor changes in freshwater storage, with a view towards informing sustainable, basin-scale water management. Significant results from this study have identified ongoing reservoir and groundwater storage depletion (defined as human-accessible water) during the drought of the last decade. Remote sensing is used to estimate additional losses to water storage within the Basin, including increases in evapotranspiration (ET) from management practices such as irrigation and urbanization.
Hydromorphology of Groundwater/Surface Water Behaviors
Groundwater/surface water interaction is a small part of the much larger, complex global water cycle; however, it is an integral threshold where multiple key interactions occur including physical groundwater dynamics, biochemical exchanges, low flow hydrology and climatic forcing unite. The importance of groundwater/surface water research derives from several concerns: 1) groundwater storage discharge to streams comprises approximately 30% of observed global runoff; 2) groundwater discharge to streams sustains aquatic ecosystems during periods of drought; and 3) groundwater storage and discharges control surface water responses during low flow periods when water resources are stringed. Research to investigate the human impact on California hydrology using advanced recession analysis and land surface models is ongoing. The results of this study are vital to characterizing the intensifying and potentially dramatic effects on the availability of freshwater resources as a result of human impacts and climate change.
Modeling the Arteries of the Earth
It is well understood that water is the backbone of human life and civilization. Despite its inherent importance, our ability to understand how water moves through the Earth's landscape remains limited. Such knowledge is required for efficient management of our current water resources and to prepare for a sustainable water future. The goals of this research are: 1) to develop computer models that simulate the flow of water in large networks of rivers and reservoirs; and 2) to use these models to understand human impacts on the terrestrial water cycle. Research results can be adapted for real-time management of water resources.
Adaptive Godunov-based Flood Inundation Modeling
Expanding urbanization trends and climate change effects mean increases in extreme flooding around the world, highlighting the great need for effective flood modeling. The goals of this research are: 1) to develop a versatile tool for prediction of flood inundation using a mixed mesh Godunov-based scheme; 2) to extend a process-based 2D urban flood model to catchment scale by utilizing porous shallow water equations; 3) to develop sub-grid hydrodynamic model based Godunov type scheme for large scale simulation in data sparse areas; and 4) to evaluate large scale hydrologic and hydrodynamic modeling. The developed model will be used to support emergency management directly through flood forecasting, and to effectively plan for imminent flooding by identifying the best risk reduction measures through comparative analysis of the socio-economic and environmental consequences of each option.
Hydrologic Data Portal
Some data sets are not easily obtainable and distributable due to their scale and complexity, such as basin climatology, precipitation and terrestrial water storage. For increased accessibility to these inaccessible data sets, the UCCHM has implemented a Hydrologic Data Portal (HDP) through a web browser, which allows for the visualization of these hydrologic data sets. A set of data visualization features is provided to users, enabling them to search, retrieve, analyze, integrate, organize and map data. Up-to-date information technologies are incorporated into the HDP to create ease in navigating large scale data. The next steps for the HDP will be to expand the scope of data sets available to users and to offer the ability to download such data sets.
Teacher Professional Development
In February and August 2010, the American Museum of Natural History (AMNH) sponsored the GRACE Educational Workshop and Professional Development course for High School and Middle School teachers in the greater New York area. The goal was to relate remote sensing hydrologic data from GRACE to the teachers in a format they could take back to their classrooms. AMNH asked the UC Center for Hydrologic Modeling (UCCHM) to help develop and present the material to the teachers. With the development of a short GRACE based film, a dynamic data interface, and access to actual scientific data, the teachers learned the material and created their own lesson plans to take back to their students. The AMNH Workshop is centered on the basic knowledge of the hydrologic cycle, GRACE fundamentals and three case studies (California, India and the Ice Sheets). UCCHM gave PowerPoint presentations to introduce these items and provided Excel spreadsheets with assignments for hands on experience with the data. Once the teachers manipulated the data to produce the same results they recognized in scientific journals, we discussed the socioeconomic and political implications of the data. The UCCHM still has contact with certain high school teachers to continue to bring new information into the classroom. The interaction between high school teachers, UCCHM scientists and the AMNH proved to be a success by introducing present day science challenges to the attention of high school students who will have the biggest impact on future environmental conditions.
Central Valley groundwater and outreach
On August 2, 2010, the UC Center for Hydrologic Modeling (UCCHM) sponsored an event entitled, “Working Toward Sustainable Water Solutions to Support Central Valley Farmers,” at the UC Merced Center in Fresno, California. The high rates of groundwater depletion we have seen from GRACE led us to this event. The goal of the event was to better understand the water supply issues in California by promoting dialogue between the academic, agricultural, and citizen stakeholders of the Central Valley. We, as scientists, wanted to gain an on-the-ground perspective of the circumstances in the Central Valley, how water-use decisions are made from an agricultural perspective, and how we can focus our research to improve water management practices. The Central Valley stakeholders wanted to describe what it is like to live and work in the Central Valley in a water-limited state, providing a “human” context to our research. Some of the attendees included Central Valley farmers; county farm bureau groups including Tulare, San Joaquin, Merced, and Fresno counties; farmer representative groups including the California Latino Water Coalition, the California Farm Bureau Federation, the California Grape & Tree Fruit League, and the California Farm Water Coalition; policy makers; and Center scientists.
We learned that the farmers’ water allocations from the California Department of Water Resources are often received after crops have to be planted, which results in an increased dependence on groundwater in below-average allocation years. As a result, UCCHM and California’s academic community is presented with the challenge of working with state decision-makers to improve the forecasting and modeling systems that are used to make allocation decisions, in order to better match the farmers’ needs. Another opportunity presented by the agricultural community was for the scientific community to provide farms with improved soil moisture monitoring for more efficient irrigation, in exchange for water use and groundwater level data. The next step for UCCHM is to establish collaboration with the California Department of Water Resources, while continuing communication with the agricultural stakeholders.
The water cycle is an intricate system on its own. Add human influence to the equation, and the complexity of water moving throughout the environment is amplified. Governmental regulations are a necessary safeguard for the water cycle, ensuring that human water demand and environmental integrity are in balance. The UCCHM strongly believes in the need to base these regulations on the best available science. There are clear societal applications to the research conducted at the UCCHM, giving the Center the unique opportunity to both advance scientific knowledge and assist decision-makers. Connecting research results to local, state and federal decision-makers is a top priority for the Center. Insofar government advising has taken place through regular Congressional testimonies and briefings; speaking directly with Congressional members in the House and Senate; presentations to Congressional Committees including the House Armed Services Committee and the Senate Committee on Energy and Natural Resources; briefings for federal agencies including the U.S. State Department, U.S. Department of the Interior, Office of Science & Technology Policy and the World Bank; and stakeholder briefings including "Working Towards Sustainable Water Solutions to Support Central Valley Farmers" in Fresno, California. The UCCHM believes that an open dialogue with decision-makers is crucial to understanding how to most effectively utilize research results to address societal needs.
Water Diplomacy in the Middle East
Through a joint collaboration with researchers and practitioners in the Middle East, the UCCHM will develop a remote-sensing based decision-support tool. The tool will be created through two-way data exchanges and collaborative learning. The goals of this research are: 1) to advance the state of remote sensing-based hydrologic science by downscaling GRACE to a higher resolution such that it can be used at a management scale; and 2) to analyze potential hydrologic and economic benefits of implementing successful water efficiency strategies from the Middle East to California's Central Valley. The communication of findings to decision-makers in Israel, the Palestinian Authority, Jordan and California will be ongoing throughout this project. This project will allow for a region-specific analysis of water-use and practices, the efficient application of findings to "real-world" situations and a renewed sense of effective communication between decision-makers concerning water management practices and policies. Although the initial scope of the project will focus on Israel and California, the resulting decision-support tool and methods will be applicable to water management on a global scale.
Water Diplomacy in East Africa
UCCHM is organizing meetings to coordinate joint collaboration with researchers and Water Ministries in East Africa (Kenya, Uganda and Tanzania) to support hydrologic modeling efforts in the region. Goals of the research are: 1) characterize the spatial and temporal trends in surface water and groundwater storage over East Africa, 2) identify the impact of groundwater withdrawals on streamflow and surface water storage and 3) depict the sensitivity of water resources to future variations due to climate and anthropogenic change. Key steps to meet research goals include collection of data for model calibration/validation; thus, our initial efforts focus on meetings to acquire data in addition to promoting relationships with water managers. The resulting model will be applicable to water management for East Africa but will highlight the uncertainty in projected water resources impacted by human interactions.
ARkStorm: Extreme flooding in California
An ARkStorm (for Atmospheric River 1000 Storm) is a hypothetical but scientifically realistic "extreme storm" scenario developed and documented by the USGS. It is required to prevent extreme flood disasters and establish flood inundation map as non-structural measures against a plausible ARkStrom in California. The accurate numerical model such as BreZo can be a useful tool for flood control against extreme flooding in California.
BreZo is a 2D flood inundation model and being optimized for wetting and drying applications involving natural topography and runs on an unstructured grid of hybrid cells, making it possible to efficiently represent and simulate arbitrary topography in California. Flood extents, water depths, velocities, and durations by ARkStorm scenarios in California will be issued on Google Earth KMZ files based on the results of BreZo and ArcGIS.
Statewide ET mapping
Evapotranspiration (ET) is a key component of the water cycle; changes in ET directly impact runoff and water availability for urban, agricultural, and environmental uses. ET may change significantly regionally with anticipated climate change. Timely observations of ET and understanding of mechanisms controlling ET are needed to predict water availability for human and environmental uses. Unfortunately, ET is the most uncertain and poorly measured component of the hydrologic cycle. Recent advances in satellite remote sensing and surface meteorological measurements have enabled near-realtime spatial ET products to be developed, which could improve assessments of current and future water availability. California’s competing demands for water and hydrologic variability make these types of products especially important. However, California’s vegetation types and topographic variation confound the biophysical relationships that underpin these products.
My collaborative role with UCCHM is twofold. First, I am comparing an ensemble of ET products against a well-constrained water budget in the Central Valley that is one of the richest agricultural regions in the world and which has been undergoing well documented groundwater depletion. I implemented a surface energy balance ET model to create one of the products. I integrated the ET products with gravimetric estimates of groundwater depletion to assess surface water consumption by irrigated agriculture. My second role is a statewide implementation and comparison of ET methods. I implemented four ET methods on a common grid statewide. Currently I’m comparing the performance of these approaches across California’s ten hydrologic regions. I will assess what approach works best in each region and controls (e.g. vegetation cover, vegetation seasonality, topography, and elevation) on ET in each region.