Weather, Water and Society on the Colorado River: CW3E Explores the Yampa River Basin

CW3E Publication Notice

Weather, Water and Society on the Colorado River: CW3E Explores the Yampa River Basin

June 11, 2018

The Yampa River is one of the wildest remaining major tributaries of the Colorado River and supports a rich ecosystem, local agriculture and ranching, and a robust recreation industry. It also provides crucial water supplies to local stakeholders and locations as far removed as Arizona and Southern California. A multitude of environmental and societal needs influence water management and conservation decisions in the Yampa River, and are pertinent to other watersheds around the American West. Similarly, regional weather and climate extremes help shape the basin’s hydrology, environment, and water resources.

This June, CW3E travelled to Steamboat Springs, Colorado, for the Yampa Basin Workshop. This was a community-oriented event organized by CW3E and partners from Colorado Mountain College, Yampa Sustainability Council, Friends of the Yampa, and Wyndham Resorts. During the Workshop, participants examined the Yampa River Basin through the lens of weather, environment, and culture. The workshop included talks by local experts, discussion panels, afternoon field learning, and a community event. After building a foundation on the region’s history and environment, we explored the various demands on the Yampa’s water, and learned how these needs are met and where challenges remain. This dialogue with the local community introduced graduate students, post-doctoral scholars, researchers, staff and faculty from CW3E to the Yampa Basin. Drawing from the community’s historical knowledge and expertise on the challenges and successes of conservation and use practices on the Yampa, the Workshop has prompted new research directions for CW3E that will support weather and water decision-making processes in the Colorado River Basin and California.

CW3E group photo on the Fetcher Ranch, June 7th, 2018. (Pictured left to right, Marty Ralph, Rachel Weihs, Lindsey Jasperse, Anna Wilson, Rob Hartman, Kara Voss, Douglas Alden, Meredith Fish, Brian Kawzenuk, Leah Campbell, Mike Sierks, Will Chapman, Ali Hamidi, Aneesh Subramanian, and Tamara Shulgina). Photo credit: Rachel Weihs

CW3E’s Anna Wilson chairs a panel discussion at the Yampa River Rendezvous at the Colorado Mountain College in Steamboat Springs, CO, June 5th, 2018. Pictured: Mike Meyers (National Weather Service), Jon Rutz (CW3E/NWS Western Region), Gannet Hallar (Storm Peak Lab, U. of Utah), Becky Bolinger (Colorado State University). Photo credit: Rachel Weihs

George Stanko (forefront) talks to the CW3E team on Stanko Ranch near the Yampa River, June 5th, 2018. Photo credit: Rachel Weihs

CW3E Participates in Second ARTMIP Workshop

CW3E Participates in 2nd ARTMIP Workshop

April 26, 2018

The 2nd Atmospheric River Tracking Method Intercomparison Project (ARTMIP) Workshop was recently held in Gaithersburg, Maryland. The ARTMIP, started in 2017, is an effort to quantify the uncertainty in AR climatology, precipitation, and related impacts that arise because of different AR tracking methods, and how these AR-related metrics may change in the future. It also aims to provide guidance regarding the advantages and disadvantages of these different AR tracking methods, and which of these methods are best suited to answer certain scientific questions. Several members of CW3E are actively participating in ARTMIP and attended the workshop, including, Director Marty Ralph, Brian Kawzenuk, Aneesh Subramanian, Tamara Shulgina, and Anna Wilson.

The purpose and goals of the workshop were:

  • Discuss Tier 1 catalogues in context of science questions defined in the 1st ARTMIP workshop
  • Discuss Tier 1 analysis for the science overview paper
  • Discuss metrics, and adjust if necessary, and begin to formulate guidance on algorithmic choices based on Tier 1 results
  • Discuss and organize Tier 2 catalogue details and future studies

A main outcome from the workshop included the discussion of Tier 1 analysis and two publications from Tier 1. The first, an outline on the experimental design led by Christine Shields (NCAR), is currently under review with GMD. The second, led by Jon Rutz (NOAA), will provide overviews of the results from Tier 1. Another main outcome from the workshop was the discussion and planning of three publications from Tier 2 datasets: high-resolution climate change model runs, CMIP5 climate runs, and historical reanalyses comparison to the MERRA-2. At least eight other additional publications were discussed as well, including topics such as extreme precipitation, ENSO, ARs in polar regions, measures of internal variability, data resolution sensitivity, and more. Next steps for the ARTMIP include completion of the Tier 1 overview paper and beginning of Tier 2 catalog generation and analyses.

Workshop Participants (left to right): Jon Rutz (NOAA), Roger Pierce (NOAA), Ruby Leung (PNNL), Phu Nguyen (UC Irvine), Irina Gorodetskaya (Univ. Aveiro), Helen Griffith (Univ. Reading), Christine Shields (NCAR), Brian Kawzenuk (UCSD), Alexandre Ramos (Univ. Lisbon), Marty Ralph (UCSD), Juan Lora (UCLA), Gary Geernaert (DOE), Ashley Payne (Univ. Michigan), Elizabeth McClenny (UC Davis), Travis O’Brien (LBNL), Naomi Goldenson (UCLA), Daniel Walton (UCLA), Vitaliy Kurlin (LBNL), Aneesh Subramanian (UCSD), Tamara Shulgina (UCSD), Yang Zhou (Stony Brook Univ.), Bin Guan (UCLA), Renu Joesph (DOE), Michael Wehner (LBNL), Maximilliano Viale (Univ. Chile), Paul Ullrich (UC Davis; not pictured), Swen Brands (Meteogalicia; not pictured), Anna Wilson (UCSD; not pictured).

For more information on ARTMIP, visit the ARTMIP website.

CW3E Graduate Student Attends the RIKEN International School on Data Assimilation Workshop

CW3E Represented at the National Council for Science and the Environment National Conference and Global Forum

February 2, 2018

Third year PhD student, Meredith Fish, was accepted to attend the RIKEN International School on Data Assimilation for a workshop in 2018 in Kobe, Japan on full scholarship. RIKEN is Japan’s largest research institute and houses its K computer, ranked number one for 5 consecutive years on the Graph500 supercomputer ranking. Research at the Advanced Institute for Computational Science at RIKEN focuses on weather forecasting, earthquake/tsunami forecasting, space science, drug discovery and manufacturing development.

During the workshop students attended lectures and participated in hands-on sessions lead by top leaders in data assimilation such as Stephen Penny (NCEP), Eugenia Kalnay (U. of Maryand), Gregory Hakim (U. Washington), Sebastian Reich (U. Reading) and Henry Abarbanel (UCSD). Lecture topics included the mathematical background of data assimilation, geoscience applications, data assimilation within a toy model, machine learning and coupled human-earth systems.

This workshop has prepared Meredith to use data assimilation in her research and actively participate in the AR Recon field campaign, which is attempting to leverage data assimilation techniques to quantify uncertainties in forecasts using targeted observations.

Meredith standing in from of the Advanced Institute for Computational Sciences at RIKEN in Kobe, Japan.

CW3E Represented at the National Council for Science and the Environment National Conference and Global Forum

CW3E Represented at the National Council for Science and the Environment National Conference and Global Forum

January 29, 2018

On January 23-24, 2018, the National Council for Science and the Environment (NCSE) held its 18th National Conference and Global Forum: The Science, Business, and Education of Sustainable Infrastructure: Building Resilience in a Changing World, at the Hyatt Regency Crystal City near Washington, DC. Shown above, Rob Hartman representing CW3E, describes Atmospheric Rivers, AR research, and FIRO for Lake Mendocino during a panel discussion entitled “Innovations and Success Stories in Sustainable Water Management at the Federal, State, and Local levels. The panel was co-chaired by Dr. Robert Wilkinson (UCSB, seated far left) and David Berry. Panelists included (right to left) Carl Morrison, Dale Roberts (SCWA), Shirley Zane (Sonoma County Commissioner), Robin Webb (NOAA/OAR), and Rob Hartman (representing CW3E, standing). NCSE attendees come primarily from research, education and policy sectors, with representatives from federal, state, and local agencies along with university researchers. Many in attendance had not been exposed to the concept and importance of ARs in the West or the research effort to demonstrate the value of FIRO in the Russian River Basin.

CW3E Hosts California DWR Winter Outlook Workshop

CW3E Hosts California DWR Winter Outlook Workshop

November 6, 2017

CW3E hosted the annual California Department of Water Resources Winter Outlook Workshop (WOW) from Nov. 1-3, at Scripps Institution of Oceanography. The purpose of the workshop is to highlight the latest science in seasonal to subseasonal (S2S), 1-month to 3-month, atmospheric forecasting. This timescale bridges the gap between weather and climate prediction. The meeting was organized by Jeanine Jones, ‎Interstate Resources Manager, and covered a variety of topics including paleoclimate, week three predictions, atmospheric rivers (ARs), summer North American monsoon, new forecasting tools, and drought.

During the first day, Dave Meko, from University of Arizona, discussed paleodrought in Southern California and how this compared to paleodrought in Northern California and in the Colorado River Basin. The second day of the workshop highlighted recent accomplishments in subseasonal to seasonal forecasting. Dr. David DeWitt, NCEP CPC Director, presented on the S2S activities on-going at the National Weather Service (NWS) Climate Prediction Center (CPC). Dr. Marty Ralph, Director of CW3E, gave an overview of the activities at CW3E related to observations, modeling and S2S prediction ARs. This was followed by a session chaired by Dr. Duane Waliser and Dr. Aneesh Subramanian on current S2S activities at CW3E and an experimental CW3E week-3 AR outlook product. The session had three talks presented by Dr. Alexander Gershunov, Dr. Michael DeFlorio, and Dr. Aneesh Subramanian on the experimental CW3E week-3 AR outlooks and the multi-pronged effort to design and evaluate the product. The day ended with presentation by Yolande Serra, from the University of Washington, on the dynamics and predictability of the summer monsoon. The third and final day began with a presentation on the influence of ARs in the Colorado River Basin as well an historical perspective on atmospheric river maps by Jon Rutz, National Weather Service. The last presentation of the day was by Dan Cayan on how various atmospheric patterns can lead to drought in the western U.S. WOW provided an opportunity for CW3E researchers and collaborators to share their latest advancements in subseasonal to seasonal forecasting and discuss future research collaboration and needs.

CW3E Director, Marty Ralph, discusses the research and activities at CW3E during the DWR WOW.

During the workshop Jeanine Jones also presented Department of Water Resources Climate Service Awards to Dr. Jason Cordeira, Plymouth State University, Dr. Duane Waliser, NASA JPL and Dr. Dave Meko, University of Arizona. The awards highlight the three individuals’ contribution to climate science as it applies to DWR operations. Jason Cordiera, a close collaborator of CW3E spoke of the honor, “My collaboration with CW3E has led to the synergistic development of many weather forecast tools that have benefited and informed water resource management and related impact-based decision support. Receipt of the CA DWR Climate Science Service Award reflects the dedication of many individuals at CW3E and Plymouth State who support and provide invaluable resources to maintain a productive research and application environment. Thank you to the CA DWR for the honor and I look forward to continued collaboration in pursuit of improving our ability to understand and forecast hydrological extremes”.

Recipients of the Department of Water Resources Climate Service Awards, presented at the WOW. From left, Dr. Duane Waliser, NASA JPL, Dr. Dave Meko, University of Arizona, and Dr. Jason Cordeira, Plymouth State University.

CW3E, UCAR, and NCAR Meet to Discuss West-WRF Regional Model Development

CW3E, UCAR, and NCAR Meet to Discuss West-WRF Regional Model Development

October 9, 2017

On 4-5 October 2017, CW3E had the privilege of hosting visitors from NCAR and UCAR to discuss the development and implementation of West-WRF, the regional forecast model that CW3E is developing focusing on extreme precipitation. The team from UCAR and NCAR included Bill Kuo, the director of UCAR Community Programs, who also helped lead the development of WRF. Chris Davis, NCAR associate director and leader of the Mesoscale and Microscale Meteorology (MMM) Laboratory also attended, along with, David Gill, Jake Liu, and Wei Wang, WRF experts in computation, data assimilation, and modeling, respectively.

The first day of the two day visit began with CW3E director, Marty Ralph, briefing the NCAR/UCAR visitors on CW3E, and how West-WRF supports the mission and goals of the center. After this introduction, CW3E researchers and staff had the opportunity to learn about best practices with respect to WRF computation, modeling, and data assimilation, as well as the new MPAS modeling system. The entire CW3E group had lunch with the NCAR/UCAR visitors and had a chance to hear all the CW3E updates including on AR reconnaissance, publications, and instrument deployments.

After lunch, the CW3E West-WRF team shared the current applications and status of the West-WRF development with the UCAR/NCAR team. The afternoon ended with Bill Kuo giving the CASPO seminar on assessment of the impacts of assimilation of COSMIC radio occultation measurements in typhoon forecasts. The second day of the visit, allowed for detailed discussions on many of the technical aspects of West-WRF development and applications. The UCAR/NCAR team provided recommendations to the CW3E researches and staff on ways to improve the implantation of West-WRF as well as design experiments. In addition the groups discussed ways for the CW3E team to provide feedback in the WRF development at NCAR/UCAR through sharing new code for verification metrics and scientific and technical advancements made through recent experiments. The meeting was a very productive initial collaboration between CW3E and UCAR/NCAR and we are looking forward to many more. The engagement of UCAR and NCAR in supporting one of its member institutions technical development efforts is greatly appreciated.

Atmospheric Rivers: Recent Developments and Applications in California

Atmospheric Rivers: Recent Developments and Applications in California

May 19, 2017

In Sacramento on Tuesday, May 23rd, CW3E director, F. Martin Ralph will be presenting a seminar about atmospheric rivers and their impacts to California legislative and agency staff. The seminar, Atmospheric Rivers: Recent Developments and Applications in California, will provide updates on the impacts of ARs on the current water year and the ongoing research to better understand and better forecast ARs. Dr. Ralph is looking forward to sharing all of the exciting research being done at CW3E with the group.

May 31 – June 2 Big Data and The Earth Sciences: Grand Challenges Workshop

May 31 – June 2 Big Data and The Earth Sciences: Grand Challenges Workshop

April 17, 2017

Abstract deadline extended to April 21st

The Center for Western Weather and Water Extremes (CW3E) of UC San Diego’s Scripps Institution of Oceanography and the Pacific Research Platform (PRP) is excited to announce the organization of a workshop focused on earth sciences and information technology at the University of California San Diego. The workshop is a three-day Grand Challenges workshop May 31 to June 2 in La Jolla, Calif., on the topic of “Big Data and the Earth Sciences”.

CW3E is focused on advancing science and technology to support the unique information needs related to western U.S. extreme weather and water events, such as California’s recent flooding and multi-year drought and associated potential for subseasonal-to-seasonal forecasting. PRP is a consortium of universities in the western U.S. that is building a “science-driven, high-capacity data-centric freeway system on a large regional scale.” Funded by the National Science Foundation, PRP is based in the California Institute for Telecommunications and Information Technology (Calit2), a partnership of UC San Diego and UC Irvine. The workshop will take place in UC San Diego’s Atkinson Hall, headquarters of the Qualcomm Institute (the UCSD division of Calit2).

The goal of the The Big Data and Earth Sciences: Grand Challenges Workshop is to bring thought leaders in Big Data and Earth Sciences together for a three day, intensive workshop to discuss what is needed to advance our understanding and predictability of the Earth systems and to highlight key technological advances and methods that are readily available or in the final stages of development.

Sessions will include:

  • Big data collaborations;
  • Big data research platforms, networks, technologies and visualization;
  • Big data and predictability challenges in earth science data;
  • Pattern detection, segmentation and object recognition for earth sciences;
  • Structuring unstructured data in the earth sciences; as well as
  • Data mining and discovery, machine learning and predictive modeling.

For more information please visit:


Official workshop website:

Please send abstracts to

Abstracts are restricted to one page. Please include the abstract title, authors’ names and affiliations. A word document or .pdf is preferred.

CW3E Participates in Water in the West: A Science Policy Roundtable

CW3E Participates in Water in the West: A Science Policy Roundtable

December 10, 2016

CW3E was represented in a December 8, 2016 panel discussion hosted by UCSD’s School of Global Policy and Strategy (GPS)’s Science Policy Fellows Program and SIO’s Science Policy Discussion Group, titled “Water in the West: A Science Policy Roundtable”. The purpose of the event was to bring together our different communities and explore the sources of California’s water supply, how water supply can change, how it is used throughout the state and best practices for optimal regulation of its use.

CW3E director Dr. F. Martin Ralph acted as moderator. Other panel members were Dr. Jennifer Burney of GPS, Sandra Kerl of the San Diego County Water Authority, and Dr. Dan Cayan of SIO and a CW3E collaborator. Dr. Scott Sellars, the leader of the Science Policy Discussion Group, was involved in organizing the event. Other CW3E postdocs and graduate students assisted with logistics. The attendance was just over 100 people, with a very engaged audience. Questions were asked on topics ranging from specific projects run by the SD County Water Authority, to potential changes to academic funding sources with the incoming federal administration, to questions on groundwater and atmospheric rivers science. The event was recorded and can be viewed here.

More details are available in the GPS news story.

At podium: Marty Ralph (Scripps/CW3E); Left to right at table: Sandra Kerl (San Diego County Water Authority), Dan Cayan (Scripps/CW3E and USGS), Jennifer Burney (GPS)

CW3E Hosts Winter Outlook Workshop with California DWR

CW3E Hosts Winter Outlook Workshop with California DWR

November 18, 2016

The California Department of Water Resources (CDWR) and CW3E led a working meeting with researchers at the Scripps Institution of Oceanography in La Jolla, November 16-18, 2016. The workshop focused on efforts to improve sub-seasonal to seasonal prediction of precipitation, which could help agencies better manage water resources.

“We’d all like to know if 2017 will be wet or dry, but determining that is scientifically difficult. We’re trying to emphasize the need for prioritizing this research in the science community,” said Jeanine Jones, Interstate Resources Manager at CDWR.

Participants from the following agencies were in attendance: CW3E/Scripps, CDWR, Sonoma County Water Agency (SCWA), National Center for Atmospheric Research (NCAR), Natonal Weather Service (NWS), Western States Federal Agency Support Team (WestFAST), National Oceanic and Atmospheric Administration (NOAA), Plymouth State University (PSU), Oregon State University (OSU), University of California, Los Angeles (UCLA), Salt River Project (SRP), Climate Assessment for the Southwest (CLIMAS), Desert Research Institute (DRI), and Metropolitan Water District of Southern California (MWD).

Images courtesy DWR Photography – Florence Low