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Robert S. Webb
and
Francisco E. Werner
Full access
Michael G. Jacox
,
Michael A. Alexander
,
Nathan J. Mantua
,
James D. Scott
,
Gaelle Hervieux
,
Robert S. Webb
, and
Francisco E. Werner
Full access
Donald Murray
,
Andrew Hoell
,
Martin Hoerling
,
Judith Perlwitz
,
Xiao-Wei Quan
,
Dave Allured
,
Tao Zhang
,
Jon Eischeid
,
Catherine A. Smith
,
Joseph Barsugli
,
Jeff McWhirter
,
Chris Kreutzer
, and
Robert S. Webb

Abstract

The Facility for Weather and Climate Assessments (FACTS) developed at the NOAA Physical Sciences Laboratory is a freely available resource that provides the science community with analysis tools; multimodel, multiforcing climate model ensembles; and observational/reanalysis datasets for addressing a wide class of problems on weather and climate variability and its causes. In this paper, an overview of the datasets, the visualization capabilities, and data dissemination techniques of FACTS is presented. In addition, two examples are given that show the use of the interactive analysis and visualization feature of FACTS to explore questions related to climate variability and trends. Furthermore, we provide examples from published studies that have used data downloaded from FACTS to illustrate the types of research that can be pursued with its unique collection of datasets.

Free access
Donald Murray
,
Andrew Hoell
,
Martin Hoerling
,
Judith Perlwitz
,
Xiao-Wei Quan
,
Dave Allured
,
Tao Zhang
,
Jon Eischeid
,
Catherine Smith
,
Joseph Barusgli
,
Jeff McWhirter
,
Chris Kreutzer
, and
Robert S. Webb
Full access
Julie A. Vano
,
Bradley Udall
,
Daniel R. Cayan
,
Jonathan T. Overpeck
,
Levi D. Brekke
,
Tapash Das
,
Holly C. Hartmann
,
Hugo G. Hidalgo
,
Martin Hoerling
,
Gregory J. McCabe
,
Kiyomi Morino
,
Robert S. Webb
,
Kevin Werner
, and
Dennis P. Lettenmaier

The Colorado River is the primary water source for more than 30 million people in the United States and Mexico. Recent studies that project streamf low changes in the Colorado River all project annual declines, but the magnitude of the projected decreases range from less than 10% to 45% by the mid-twenty-first century. To understand these differences, we address the questions the management community has raised: Why is there such a wide range of projections of impacts of future climate change on Colorado River streamflow, and how should this uncertainty be interpreted? We identify four major sources of disparities among studies that arise from both methodological and model differences. In order of importance, these are differences in 1) the global climate models (GCMs) and emission scenarios used; 2) the ability of land surface and atmospheric models to simulate properly the high-elevation runoff source areas; 3) the sensitivities of land surface hydrology models to precipitation and temperature changes; and 4) the methods used to statistically downscale GCM scenarios. In accounting for these differences, there is substantial evidence across studies that future Colorado River streamflow will be reduced under the current trajectories of anthropogenic greenhouse gas emissions because of a combination of strong temperature-induced runoff curtailment and reduced annual precipitation. Reconstructions of preinstrumental streamflows provide additional insights; the greatest risk to Colorado River streamf lows is a multidecadal drought, like that observed in paleoreconstructions, exacerbated by a steady reduction in flows due to climate change. This could result in decades of sustained streamflows much lower than have been observed in the ~100 years of instrumental record.

Full access
Maude Dinan
,
Emile Elias
,
Nicholas P. Webb
,
Greg Zwicke
,
Timothy S. Dye
,
Skye Aney
,
Michael Brady
,
Joel R. Brown
,
Robert R. Dobos
,
Dave DuBois
,
Brandon L. Edwards
,
Sierra Heimel
,
Nicholas Luke
,
Caitlin M. Rottler
, and
Caitriana Steele
Full access
Allen B. White
,
Brad Colman
,
Gary M. Carter
,
F. Martin Ralph
,
Robert S. Webb
,
David G. Brandon
,
Clark W. King
,
Paul J. Neiman
,
Daniel J. Gottas
,
Isidora Jankov
,
Keith F. Brill
,
Yuejian Zhu
,
Kirby Cook
,
Henry E. Buehner
,
Harold Opitz
,
David W. Reynolds
, and
Lawrence J. Schick

The Howard A. Hanson Dam (HHD) has brought flood protection to Washington's Green River Valley for more than 40 years and opened the way for increased valley development near Seattle. However, following a record high level of water behind the dam in January 2009 and the discovery of elevated seepage through the dam's abutment, the U.S. Army Corps of Engineers declared the dam “unsafe.” NOAA's Office of Oceanic and Atmospheric Research (OAR) and National Weather Service (NWS) worked together to respond rapidly to this crisis for the 2009/10 winter season, drawing from innovations developed in NWS offices and in NOAA's Hydrometeorology Test-bed (HMT).

New data telemetry was added to 14 existing surface rain gauges, allowing the gauge data to be ingested into the NWS rainfall database. The NWS Seattle Weather Forecast Office produced customized daily forecasts, including longer-lead-time hydrologic outlooks and new decision support services tailored for emergency managers and the public, new capabilities enabled by specialized products from NOAA's National Centers for Environmental Prediction (NCEP) and from HMT. The NOAA Physical Sciences Division (PSD) deployed a group of specialized instruments on the Washington coast and near the HHD that constituted two atmospheric river (AR) observatories (AROs) and conducted special HMT numerical model forecast runs. Atmospheric rivers are narrow corridors of enhanced water vapor transport in extratropical oceanic storms that can produce heavy orographic precipitation and anomalously high snow levels, and thus can trigger flooding. The AROs gave forecasters detailed vertical profile observations of AR conditions aloft, including monitoring of real-time water vapor transport and comparison with model runs.

Full access
Randall M. Dole
,
J. Ryan Spackman
,
Matthew Newman
,
Gilbert P. Compo
,
Catherine A. Smith
,
Leslie M. Hartten
,
Joseph J. Barsugli
,
Robert S. Webb
,
Martin P. Hoerling
,
Robert Cifelli
,
Klaus Wolter
,
Christopher D. Barnet
,
Maria Gehne
,
Ronald Gelaro
,
George N. Kiladis
,
Scott Abbott
,
Elena Akish
,
John Albers
,
John M. Brown
,
Christopher J. Cox
,
Lisa Darby
,
Gijs de Boer
,
Barbara DeLuisi
,
Juliana Dias
,
Jason Dunion
,
Jon Eischeid
,
Christopher Fairall
,
Antonia Gambacorta
,
Brian K. Gorton
,
Andrew Hoell
,
Janet Intrieri
,
Darren Jackson
,
Paul E. Johnston
,
Richard Lataitis
,
Kelly M. Mahoney
,
Katherine McCaffrey
,
H. Alex McColl
,
Michael J. Mueller
,
Donald Murray
,
Paul J. Neiman
,
William Otto
,
Ola Persson
,
Xiao-Wei Quan
,
Imtiaz Rangwala
,
Andrea J. Ray
,
David Reynolds
,
Emily Riley Dellaripa
,
Karen Rosenlof
,
Naoko Sakaeda
,
Prashant D. Sardeshmukh
,
Laura C. Slivinski
,
Lesley Smith
,
Amy Solomon
,
Dustin Swales
,
Stefan Tulich
,
Allen White
,
Gary Wick
,
Matthew G. Winterkorn
,
Daniel E. Wolfe
, and
Robert Zamora

Abstract

Forecasts by mid-2015 for a strong El Niño during winter 2015/16 presented an exceptional scientific opportunity to accelerate advances in understanding and predictions of an extreme climate event and its impacts while the event was ongoing. Seizing this opportunity, the National Oceanic and Atmospheric Administration (NOAA) initiated an El Niño Rapid Response (ENRR), conducting the first field campaign to obtain intensive atmospheric observations over the tropical Pacific during El Niño.

The overarching ENRR goal was to determine the atmospheric response to El Niño and the implications for predicting extratropical storms and U.S. West Coast rainfall. The field campaign observations extended from the central tropical Pacific to the West Coast, with a primary focus on the initial tropical atmospheric response that links El Niño to its global impacts. NOAA deployed its Gulfstream-IV (G-IV) aircraft to obtain observations around organized tropical convection and poleward convective outflow near the heart of El Niño. Additional tropical Pacific observations were obtained by radiosondes launched from Kiritimati , Kiribati, and the NOAA ship Ronald H. Brown, and in the eastern North Pacific by the National Aeronautics and Space Administration (NASA) Global Hawk unmanned aerial system. These observations were all transmitted in real time for use in operational prediction models. An X-band radar installed in Santa Clara, California, helped characterize precipitation distributions. This suite supported an end-to-end capability extending from tropical Pacific processes to West Coast impacts. The ENRR observations were used during the event in operational predictions. They now provide an unprecedented dataset for further research to improve understanding and predictions of El Niño and its impacts.

Full access
Gijs de Boer
,
Allen White
,
Rob Cifelli
,
Janet Intrieri
,
Mimi Hughes
,
Kelly Mahoney
,
Tilden Meyers
,
Kathy Lantz
,
Jonathan Hamilton
,
William Currier
,
Joseph Sedlar
,
Christopher Cox
,
Erik Hulm
,
Laura D. Riihimaki
,
Bianca Adler
,
Laura Bianco
,
Annareli Morales
,
James Wilczak
,
Jack Elston
,
Maciej Stachura
,
Darren Jackson
,
Sara Morris
,
V. Chandrasekar
,
Sounak Biswas
,
Benjamin Schmatz
,
Francesc Junyent
,
Jennifer Reithel
,
Elizabeth Smith
,
Katya Schloesser
,
John Kochendorfer
,
Mike Meyers
,
Michael Gallagher
,
Jake Longenecker
,
Carrie Olheiser
,
Janice Bytheway
,
Benjamin Moore
,
Radiance Calmer
,
Matthew D. Shupe
,
Brian Butterworth
,
Stella Heflin
,
Rachel Palladino
,
Daniel Feldman
,
Kenneth Williams
,
James Pinto
,
Jackson Osborn
,
Dave Costa
,
Emiel Hall
,
Christian Herrera
,
Gary Hodges
,
Logan Soldo
,
Scott Stierle
, and
Robert S. Webb

Abstract

Water is a critical resource that causes significant challenges to inhabitants of the western United States. These challenges are likely to intensify as the result of expanding population and climate-related changes that act to reduce runoff in areas of complex terrain. To better understand the physical processes that drive the transition of mountain precipitation to streamflow, the National Oceanic and Atmospheric Administration has deployed suites of environmental sensors throughout the East River watershed of Colorado as part of the Study of Precipitation, the Lower Atmosphere, and Surface for Hydrometeorology (SPLASH). This includes surface-based sensors over a network of five different observing sites, airborne platforms, and sophisticated remote sensors to provide detailed information on spatiotemporal variability of key parameters. With a 2-yr deployment, these sensors offer detailed insight into precipitation, the lower atmosphere, and the surface, and support the development of datasets targeting improved prediction of weather and water. Initial datasets have been published and are laying a foundation for improved characterization of physical processes and their interactions driving mountain hydrology, evaluation and improvement of numerical prediction tools, and educational activities. SPLASH observations contain a depth and breadth of information that enables a variety of atmospheric and hydrological science analyses over the coming years that leverage collaborations between national laboratories, academia, and stakeholders, including industry.

Open access