What is "El Niño" and what are its effects?
The term El Niño (Spanish for 'the Christ Child') refers to a warming of the ocean surface (or above-average sea surface temperatures) in the central and eastern tropical Pacific Ocean. The low-level surface winds, which normally blow from east to west along the equator (“easterly winds”), instead weaken or, in some cases, start blowing the other direction (from west to east or “westerly winds”). El Niño recurs irregularly, from two years to a decade, and no two events are exactly alike. El Niño events can disrupt normal weather patterns in the United States and globally.
Although the USGS 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.
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Severe West Coast Erosion During 2015-16 El Niño
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.
New Maps from Old Photos: Measuring Coastal Erosion
U.S. Geological Survey scientists and their coauthors from the California Coastal Records Project have found a way to use historical aerial photographs not just to see evidence of coastal erosion, but to accurately measure how much has occurred over time.
USGS Science for an El Niño Winter
El Niño is a phenomenon that occurs when unusually warm ocean water piles up along the equatorial west coast of South America. When this phenomenon develops, it affects weather patterns around the globe, including the winter weather along the west coast of North America. This unusual pattern of sea surface temperatures occurs in irregular cycles about three to seven years apart.
El Niño and La Niña will Exacerbate Coastal Hazards Across Entire Pacific
SANTA CRUZ, Calif. — The projected upsurge of severe El Niño and La Niña events will cause an increase in storm events leading to extreme coastal flooding and erosion in populated regions across the Pacific Ocean, according to a multi-agency study published today in Nature Geoscience.
ARkStorm: California’s other "Big One"
For emergency planning purposes, scientists unveiled a hypothetical California scenario that describes a storm that could produce up to 10 feet of rain, cause extensive flooding (in many cases overwhelming the state’s flood-protection system) and result in more than $300 billion in damage.
USGS Analyzes 70 Years of Coastal Cliff Retreat in California
The U.S. Geological Survey (USGS) has released a report analyzing coastal cliff retreat along more than 350 km of the California coast over a period of approximately 70 years. This study is the first comprehensive assessment of the state's historical coastal cliff retreat.
USGS Research Links Long-Term Droughts in U.S. to Ocean Temperature Variations in the North Pacific and North Atlantic
Large-scale, long-lasting droughts in the United States — such as the present one in the West — tend to be linked to warmer than normal sea surface temperatures in the North Atlantic Ocean, and not just cooling in the tropical Pacific, according to a USGS study published today in the Proceedings of the National Academy of Sciences.
Understanding Coastal Hazards— From Coastal Erosion and Storms to Sea-level Rise
U.S. Geological Survey (USGS) Congressional briefing on "Understanding Coastal Hazards" highlights how science is helping fast-growing coastal regions and communities make smart land use decisions, minimize costly losses from coastal hazards, and preserve natural resources and the environment.
From Floods and Landslides to Ecosystems...USGS Scientists Gear Up for El Nino
From the West Coast to South Florida, the U.S. Geological Survey is gearing up as part of the scientific front line in studying and reducing the impact of El Nino.
El Nino May Trigger Landslides... USGS Map Indicates Susceptibility and Incidence of Landslides
Floods, coastal erosion and heavy precipitation aren’t the only predicted consequences of the El Nino phenomena. Landslides and debris flows could happen in areas where intense rainfall occurs.
Big Sur landslide on May 20, 2017
USGS air photo of the Mud Creek landslide, taken on May 27, 2017.
2014 Landslide in Washington State
Oblique aerial photograph of the 2014 landslide in northwest Washington. This image shows the entire extent of the landslide source area and path. This event is commonly named the “Oso Landslide” in many official reports. It is also referred to as the “SR530 Landslide,” as named by Snohomish County and Washington State. Credit: Mark Reid, USGS
El Nino map
The reds and orange colors on this world map indicate warmer sea surface temperatures. The large band of warmer waters along the equator west of South America is characteristic of El Niño. Image credit: NOAA
Bluff Erosion From El Nino 2010
Bluff erosion during the 2009–10 El Niño undermined the Great Highway guardrail at the southern end of Ocean Beach, San Francisco, California. The shoreline eroded, on average, 55 meters that winter, leading to lane closures on the highway and an emergency $5-million revetment along the base of this bluff. Photo taken by Jeff Hansen, USGS, 20 January 2010.
Bluff Erosion From El Nino (2009-2010)
Bluff erosion during the 2009–10 El Niño undermined the Great Highway guardrail at Ocean Beach, San Francisco, California. The shoreline eroded, on average, 55 meters that winter, leading to lane closures on the highway and an emergency $5-million revetment along the base of this bluff.
Severe Coastal Erosion During an El Niño Storm
Severe coastal bluff erosion, along the southern end of Ocean Beach, San Francisco, California. This storm damage occurred during the 2009-2010 El Niño, which, on average, eroded the shoreline 55 meters that winter.
Severe Coastal Erosion During an El Niño Storm
Severe bluff erosion, along the southern end of Ocean Beach, San Francisco, California, including damage to the guard rail of the Great Highway (Calif. Hwy.1). The severe winter erosion led to lane closures of the highway and an emergency, $5 million revetment along the base of this bluff. This storm damage occurred during the 2009-2010 El Niño, which, on average, eroded
...(Trailer) Riding the Storm—Landslide Danger in San Francisco Bay Area
Video Highlights:
* A catastrophic 1982 rainstorm triggered 18,000 landslides in the Bay Area, claiming 25 lives and causing $66 million in property damage
* The combination of steep slopes, weak rocks, and intense winter storms make Bay Area uplands an ideal setting for landslides
*Landslides include both swift,