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USGS El Niño Web Site
ENSO-neutral conditions have returned and are favored to continue through at least the Northern Hemisphere spring 2017. https://www.climate.gov/enso
In a study released today, U.S. Geological Survey scientists and their colleagues document how the 2015-16 winter featured one of the most powerful El Niño climate events of the last 145 years.
Although the U.S. Geological Survey doesn’t directly study or forecast the weather (our sister agency, NOAA, and its National Weather Service do), the USGS studies and documents the effects and impacts of long-term climate changes and weather phenomena across the U.S. and globally. In particular, the USGS monitors streamflow, floods, landslides, erosion, sea-level rise, and many other earth processes that affect communities and that are often affected by El Niño weather patterns. USGS closely monitors these effects to assist the NWS in its responsibilities for hazard warnings and to assist communities across the country in their preparation, response, and recovery activities.
Learn more about USGS El Niño studies in this article featured as a Top Story in the USGS Newsroom.
USGS oceanographer Dan Hoover (Pacific Coastal and Marine Science Center) was interviewed by Charles Clifford of KRON4-TV for a story about coastal-cliff erosion that could occur on beaches in and near San Francisco, California, during El Niño storms this winter. Hoover met Clifford on January 12, 2016, at Mussel Rock Park in Daly City. He explained that wave energy typically increases by about 20 percent during an El Niño winter, and storm waves combined with high tides could reach the base of cliffs and cause erosion. He noted that bluffs on different beaches differ in the geology and hydrology that affect how they will fail, making them challenging to study. The interview, broadcast that night, can be viewed at:
For more information, contact Dan Hoover, firstname.lastname@example.org, 831-460-7544.
Andy O’Neill, an oceanographer and meteorologist with the USGS Pacific Coastal and Marine Science Center, explained what El Niño is and how this year’s El Niño might affect Southern California in a webinar produced by University of Southern California (USC) Sea Grant. Her half-hour presentation opened “El Niño: What to Expect for Southern California,” a professional-development webinar broadcast October 28, 2015 (see other webinars at http://dornsife.usc.edu/uscseagrant/adaptla-webinars/). O’Neill’s clear explanation of the many facets of this complex phenomenon included a description of the Coastal Storm Modeling System (CoSMoS) and its latest extreme-storm flooding projections for Southern California. Many California agencies are eager to use these projections in their El Niño planning.
For more information, contact Andy O’Neill, email@example.com,
The projected upsurge of severe El Niño and La Niña events will cause an increase in storms leading to extreme coastal flooding and erosion in populated regions across the Pacific Ocean, according to new research by USGS scientists at the Pacific Coastal and Marine Science Center and their collaborators at institutions in Australia, New Zealand, Canada, Italy, Japan, and the United States. These results are independent of projected sea-level rise, which alone could displace up to 187 million people worldwide by the end of the 21st century. Nature Geoscience published the findings on September 21, 2015.
For more information:
Winter storms modified by future climate changes, including sea-level rise, could mean costly damage to harbors, beaches, and businesses, especially during El Niño years, when atmospheric conditions bring heavy rains to the central California coast. The biggest storms tend to hit later in the year when beaches have already been heavily battered. In a populated area that relies on its coastline for much of its revenue—from people such as surfers, beach goers, sailors, kite surfers, divers, and fisherman—there is a great need to understand how big storms can shape and affect the coast. Perhaps storms will alter an important snowy plover habitat, shift a surf break, or erode natural beach protection for waterfront businesses such as those in Capitola. USGS scientists in Santa Cruz have a rare opportunity to work on these issues close to home and collect data that can affect a range of people and businesses within the Monterey Bay region. Studying these changes now will help researchers create models of future climatic changes that will erode and shape our coasts—a valuable tool for city planners, conservationists, and the tourism industry.
Northern and Central California
The USGS conducts active research on identifying the triggering mechanisms and hazards associated with landsliding. In northern and central California, research efforts have predominantly focused on the San Francisco Bay area, and a number of research products are available that showcase the landslide effects of previous large winter storms to the region, including some related to El Niño events. These reports and maps can be used as examples of what may occur during the upcoming 2015-2016 El Niño season if heavy precipitation occurs. Visit the USGS Landslide Hazard Program's web site on El Niño and Landslides in Northern and Central California.
Like the northern part of the state, southern California is well known to be susceptible to landslides. Some are triggered by earthquakes, but more frequently landslides are caused by intense and/or prolonged rainfall. Some, but not all, of the major winter storms that have caused landslide fatalities and property damage in southern California have occurred during El Niño (1997-98 info) conditions. The USGS has a long history of research to identify landslide hazards in southern California. Visit the USGS Landslide Hazard Program's web site on El Niño and Landslides in Southern California.
The Famine Early Warning Systems Network is a leading provider of early warning and analysis on food insecurity. Created by USAID in 1985 to help decision-makers plan for humanitarian crises, FEWS NET provides evidence-based analysis on some 35 countries. Implementing team members include NASA, NOAA, USDA, and USGS, along with Chemonics International Inc. and Kimetrica.
Big storms are inevitable on the central California coast, and climate change and rising sea level are expected to intensify them, particularly in El Niño years, when atmospheric conditions bring heavy rains. For safety’s sake, and to protect resources such as businesses, beaches, and harbors that bring a coastal community like Santa Cruz much of its revenue, there’s a great need to understand how big storms can shape and affect the coast. To address this need, a team of USGS scientists led by research geologists Patrick Barnard and Jonathan Warrick are running repeated surveys of beaches and the nearby ocean bottom to compile three-dimensional maps of how beaches in northern Monterey Bay change over time.
Sediment influences how hospitable water is to certain organisms. Sediment-laden waters are preferred by some wildlife species. In the San Francisco Bay Area, sediment suspended in bay and delta water has also performed the welcome function of making the water less prone to algal blooms. As the water’s sediment content has declined in the last couple of decades, its algae count has risen. This phenomenon has been most pronounced in El Niño years of heavy rain.
“The stormy conditions of the 2009-10 El Niño winter eroded the beaches to often unprecedented levels at sites throughout California and vulnerable sites in the Pacific Northwest,” said Patrick Barnard, USGS coastal geologist. In California, for example, winter wave energy was 20 percent above average for the years dating back to 1997, resulting in shoreline erosion that exceeded the average by 36 percent.
"We conclude that, if projections for an increasing frequency of extreme El Niño and La Niña events over the twenty-first century are confirmed, then populated regions on opposite sides of the Pacific Ocean basin could be alternately exposed to extreme coastal erosion and flooding, independent of sea-level rise."
"Comparisons with regional climate proxies suggest that, whereas the Intertropical Convergence Zone is the primary control on modern upwelling in Pacific Panamá, the El Niño–Southern Oscillation drove the millennial-scale variability of upwelling during the Holocene."
"During an El Niño year, mean annual egg production and mean annual clutch frequency were the highest ever reported for this species... The extraordinary annual reproductive output of this population appears to be the result of a typically high but unpredictable biomass of annual food plants at the site relative to tortoise habitat in dryer regions."
"Historically, major droughts occurred during El Niño and co-occurrences of El Niño and positive IOD events, while major flooding occurred during La Niña and co-occurrences of La Niña and negative IOD events in the basins. This observational analysis will facilitate well-informed decision making in minimizing natural hazard risks and climate impacts on agriculture, and supports development of strategies ensuring optimized use of water resources in best management practice under a changing climate."
"To demonstrate the approach, coastal change hazard zones of arbitrary confidence levels are developed for the Tillamook County (State of Oregon, USA) coastline using a suite of simple models and a range of possible climate futures related to wave climate, sea-level rise projections, and the frequency of major El Niño events."
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