For beach towns around Monterey Bay, preserving the beaches by mitigating coastal erosion is vital. Surveys conducted now and regularly in the future will help scientists understand the short- and long-term impacts of climate change, El Niño years, and sea-level rise on a populated and vulnerable coastline.
Issue

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.
What the USGS is doing
USGS scientists started baseline mapping from all-terrain vehicles (ATVs), personal watercraft, and by foot from October 20–24, 2014. They used high-precision GPS receivers carried on foot and mounted on ATVs to measure beach and swash-zone elevations (topography). They used GPS receivers and 200-kilohertz echosounders mounted on personal watercraft to measure underwater elevations (bathymetry) along transects roughly two kilometers long and perpendicular to the shore. This initial fieldwork collected a total of 513 kilometers of trackline data along the coast: 219 kilometers of personal-watercraft data, 210 kilometers of ATV data, and 84 kilometers of backpack data, from the famous Santa Cruz Lighthouse/Surfing Museum to Moss Landing.
USGS scientists now conduct regular surveys in the fall and spring each year in the Monterey Bay area, to capture seasonal fluctuations and extreme events - such as flooding from the San Lorenzo River.
Data from these regular beach and nearshore surveys, combined with video camera imagery from strategic beach locations and with tide and wave gauge data attached to local piers, scientists can generate a multi-dimensional view of what’s changing along the coast - now, and over time.
Check out the web cams:

Adding lidar for detailed mapping
Lidar stands for Light Detection and Ranging. It is similar to radar but uses laser light instead of radio waves. This instrument rotates 360 degrees and bounces a low-power laser beam safe for the naked eye off everything around it. By measuring the length of time it takes for the light to bounce off an object and return to the scanner, the scanner can capture an accurate three-dimensional measurement of the surrounding surfaces. It is capable of doing this as fast as 122,000 times each second and produces about 10 million points of data in a single rotation.
The scanner is also capable of capturing digital images of its surroundings, which can be overlaid on the points to produce a photo-realistic three-dimensional image comprising millions of points.
These millions of points make up a “point cloud” that must be translated into geographic coordinates so that USGS can create a “map” showing super-fine detail of the area it surveyed. To enable this translation, special reflectors placed in different spots on the ground with known GPS coordinates are “seen” by the instrument as it scans. By matching up the scanned reflectors to their real-world coordinates, researchers are able to rotate the entire cloud of points to its real-life layout.
Lidar sees what the human eye can see—up to about a distance of 1,400 meters. At greater distances the measurement process is slower since it takes longer for the light to return. Like the human eye, the scanner can’t see around corners or behind objects so the equipment has to be moved to different spots to create a continous map without large gaps or shadows.
The painstaking process of producing elevation maps from multiple scans and millions of points is most time-consuming when filtering out objects such as buildings, trees, and even seabirds, so they don’t show up as false elevation peaks on the beach. Since the team wants to know how the beach and its elevation changes over time, they can overlay images produced in subsequent years or after large storms to measure the differences.
Lidar has many advantages for gathering fine-scale detail to see, for example, the effects of erosion over time, but sometimes the instrument has difficulty in registering wet objects close to the ground or in the surf zone. To overcome this, the lidar data can be combined with elevation data collected using the other techniques, such as the walking surveys, ATV surveys, and bathymetry surveys. By combining all of these data, researchers can create a continuous snapshot of the bluffs, beach, surf zone, and offshore.
This research is part of the USGS project titled, “Coastal Climate Impacts.”
Explore other research topics associated with this project, below.
Coastal Climate Impacts
Dynamic coastlines along the western U.S.
Low-lying areas of tropical Pacific islands
Climate impacts to Arctic coasts
Estuaries and large river deltas in the Pacific Northwest
Related data releases are listed below.
Polycyclic aromatic hydrocarbons (PAHs) and suspended sediment concentrations in the San Lorenzo River, Santa Cruz, California, USA
Modeled extreme total water levels along the U.S. west coast
Below are publications associated with this project.
The impacts of the 2015/2016 El Niño on California's sandy beaches
Coastal knickpoints and the competition between fluvial and wave-driven erosion on rocky coastlines
Coherence between coastal and river flooding along the California coast
Can beaches survive climate change?
Doubling of coastal flooding frequency within decades due to sea-level rise
A model integrating longshore and cross-shore processes for predicting long-term shoreline response to climate change
Extreme oceanographic forcing and coastal response due to the 2015–2016 El Niño
A multimodal wave spectrum-based approach for statistical downscaling of local wave climate
Sea-level rise and coastal groundwater inundation and shoaling at select sites in California, USA
Coastal vulnerability across the Pacific dominated by El Niño-Southern Oscillation
Development of the Coastal Storm Modeling System (CoSMoS) for predicting the impact of storms on high-energy, active-margin coasts
Below are news stories associated with this project.
- Overview
For beach towns around Monterey Bay, preserving the beaches by mitigating coastal erosion is vital. Surveys conducted now and regularly in the future will help scientists understand the short- and long-term impacts of climate change, El Niño years, and sea-level rise on a populated and vulnerable coastline.
Issue
Sources/Usage: Some content may have restrictions. Visit Media to see details.Waves from an epic storm wash onto the roadway and broadside a bus, hitting the bus hard enough to push it into the oncoming lane. Luckily no one was hurt! (Photo courtesy of Santa Cruz Sentinel) 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.
Jackson Currie navigates a personal watercraft towards Santa Cruz's Main Beach, to record bathymetric data along a transect. What the USGS is doing
USGS collects beach topographic data from all-terrain vehicles like this one. USGS scientists started baseline mapping from all-terrain vehicles (ATVs), personal watercraft, and by foot from October 20–24, 2014. They used high-precision GPS receivers carried on foot and mounted on ATVs to measure beach and swash-zone elevations (topography). They used GPS receivers and 200-kilohertz echosounders mounted on personal watercraft to measure underwater elevations (bathymetry) along transects roughly two kilometers long and perpendicular to the shore. This initial fieldwork collected a total of 513 kilometers of trackline data along the coast: 219 kilometers of personal-watercraft data, 210 kilometers of ATV data, and 84 kilometers of backpack data, from the famous Santa Cruz Lighthouse/Surfing Museum to Moss Landing.
USGS scientists now conduct regular surveys in the fall and spring each year in the Monterey Bay area, to capture seasonal fluctuations and extreme events - such as flooding from the San Lorenzo River.
Data from these regular beach and nearshore surveys, combined with video camera imagery from strategic beach locations and with tide and wave gauge data attached to local piers, scientists can generate a multi-dimensional view of what’s changing along the coast - now, and over time.
Check out the web cams:
USGS scientist Alex Snyder gathers topographic data by walking beach transects northwest of Moss Landing to help researchers understand how Monterey Bay will respond to changing environmental conditions. USGS oceanographer Dan Hoover uses a GPS-equipped backpack to measure sand elevations near the mouth of the San Lorenzo River in Santa Cruz, California, January 12, 2017. Surveys like this make long-term studies of coastal change possible. Sources/Usage: Public Domain. Visit Media to see details.Marine engineering technician Pete Dal Ferro sets up a newly acquired, portable, single-beam echo sounder on the San Lorenzo River in Santa Cruz, California. The new device, called CEESCOPE, collects bathymetric (depth) data and also records features of the subsurface. All the components are easy for one person to set up and operate, with GPS and an LCD touch screen. This day survey is part of ongoing, seasonal surveys in the nearshore regions of Monterey Bay to help characterize the sediment budget of the area. Adding lidar for detailed mapping
Lidar stands for Light Detection and Ranging. It is similar to radar but uses laser light instead of radio waves. This instrument rotates 360 degrees and bounces a low-power laser beam safe for the naked eye off everything around it. By measuring the length of time it takes for the light to bounce off an object and return to the scanner, the scanner can capture an accurate three-dimensional measurement of the surrounding surfaces. It is capable of doing this as fast as 122,000 times each second and produces about 10 million points of data in a single rotation.
The scanner is also capable of capturing digital images of its surroundings, which can be overlaid on the points to produce a photo-realistic three-dimensional image comprising millions of points.
These millions of points make up a “point cloud” that must be translated into geographic coordinates so that USGS can create a “map” showing super-fine detail of the area it surveyed. To enable this translation, special reflectors placed in different spots on the ground with known GPS coordinates are “seen” by the instrument as it scans. By matching up the scanned reflectors to their real-world coordinates, researchers are able to rotate the entire cloud of points to its real-life layout.
USGS geographer Josh Logan sets up the lidar scanner near Capitola before the December 11, 2014 "Super Soaker" storm. Lidar sees what the human eye can see—up to about a distance of 1,400 meters. At greater distances the measurement process is slower since it takes longer for the light to return. Like the human eye, the scanner can’t see around corners or behind objects so the equipment has to be moved to different spots to create a continous map without large gaps or shadows.
The painstaking process of producing elevation maps from multiple scans and millions of points is most time-consuming when filtering out objects such as buildings, trees, and even seabirds, so they don’t show up as false elevation peaks on the beach. Since the team wants to know how the beach and its elevation changes over time, they can overlay images produced in subsequent years or after large storms to measure the differences.
Lidar has many advantages for gathering fine-scale detail to see, for example, the effects of erosion over time, but sometimes the instrument has difficulty in registering wet objects close to the ground or in the surf zone. To overcome this, the lidar data can be combined with elevation data collected using the other techniques, such as the walking surveys, ATV surveys, and bathymetry surveys. By combining all of these data, researchers can create a continuous snapshot of the bluffs, beach, surf zone, and offshore.
Knowing how much sand is removed and returned by big storm events can help show how waterfronts, like this one in Capitola, change with time. - Science
This research is part of the USGS project titled, “Coastal Climate Impacts.”
Explore other research topics associated with this project, below.Coastal Climate Impacts
The impacts of climate change and sea-level rise around the Pacific and Arctic Oceans can vary tremendously. Thus far the vast majority of national and international impact assessments and models of coastal climate change have focused on low-relief coastlines that are not near seismically active zones. Furthermore, the degree to which extreme waves and wind will add further stress to coastal...Dynamic coastlines along the western U.S.
The west coast of the United States is extremely complex and changeable because of tectonic activity, mountain building, and land subsidence. These active environments pose a major challenge for accurately assessing climate change impacts, since models were historically developed for more passive sandy coasts.Low-lying areas of tropical Pacific islands
Sea level is rising faster than projected in the western Pacific, so understanding how wave-driven coastal flooding will affect inhabited, low-lying islands—most notably, the familiar ring-shaped atolls—as well as the low-elevation areas of high islands in the Pacific Ocean, is critical for decision-makers in protecting infrastructure or relocating resources and people.Climate impacts to Arctic coasts
The Arctic region is warming faster than anywhere else in the nation. Understanding the rates and causes of coastal change in Alaska is needed to identify and mitigate hazards that might affect people and animals that call Alaska home.Estuaries and large river deltas in the Pacific Northwest
Essential habitat for wild salmon and other wildlife borders river deltas and estuaries in the Pacific Northwest. These estuaries also support industry, agriculture, and a large human population that’s expected to double by the year 2060, but each could suffer from more severe river floods, higher sea level, and storm surges caused by climate change. - Data
Related data releases are listed below.
Polycyclic aromatic hydrocarbons (PAHs) and suspended sediment concentrations in the San Lorenzo River, Santa Cruz, California, USA
Water from the San Lorenzo River in Santa Cruz, California, was sampled to analyze for polycyclic aromatic hydrocarbons (PAHs) and suspended sediment concentrations (SSC) during the rainy seasons from 2008 to 2019 following drought conditions. The samples were collected using a US D-95 depth-integrated water sampler deployed from a bridge-box platform beneath a pedestrian bridge For each suspendeModeled extreme total water levels along the U.S. west coast
This dataset contains information on the probabilities of storm-induced erosion (collision, inundation and overwash) for each 100-meter (m) section of the United States Pacific coast for return period storm scenarios. The analysis is based on a storm-impact scaling model that uses observations of beach morphology combined with sophisticated hydrodynamic models to predict how the coast will respond - Multimedia
- Publications
Below are publications associated with this project.
The impacts of the 2015/2016 El Niño on California's sandy beaches
The El Niño Southern Oscillation is the most dominant mode of interannual climate variability in the Pacific. The 2015/2016 El Niño event was one of the strongest of the last 145 years, resulting in anomalously high wave energy across the U.S. West Coast, and record coastal erosion for many California beaches. To better manage coastal resources, it is critical to understand the impacts of both shoAuthorsSchuyler A Smith, Patrick L. BarnardCoastal knickpoints and the competition between fluvial and wave-driven erosion on rocky coastlines
Active margin coastlines are distinguished by rock erosion that acts in two different directions: waves erode the coast horizontally or landwards, a process that creates sea cliffs; and rivers and streams erode the landscape vertically via channel incision. The relative rates of each process exert a dominant control on coastline morphology. Using a model of river channel incision and sea-cliff retAuthorsPatrick W. Limber, Patrick L. BarnardCoherence between coastal and river flooding along the California coast
Water levels around river mouths are intrinsically determined by sea level and river discharge. If storm-associated coastal water-level anomalies coincide with extreme river discharge, landscapes near river mouths will be flooded by the hydrodynamic interactions of these two water masses. Unfortunately, the temporal relationships between ocean and river water masses are not well understood. The coAuthorsKingsley O. Odigie, Jonathan WarrickCan beaches survive climate change?
Anthropogenic climate change is driving sea level rise, leading to numerous impacts on the coastal zone, such as increased coastal flooding, beach erosion, cliff failure, saltwater intrusion in aquifers, and groundwater inundation. Many beaches around the world are currently experiencing chronic erosion as a result of gradual, present-day rates of sea level rise (about 3 mm/year) and human-drivenAuthorsSean Vitousek, Patrick L. Barnard, Patrick W. LimberDoubling of coastal flooding frequency within decades due to sea-level rise
Global climate change drives sea-level rise, increasing the frequency of coastal flooding. In most coastal regions, the amount of sea-level rise occurring over years to decades is significantly smaller than normal ocean-level fluctuations caused by tides, waves, and storm surge. However, even gradual sea-level rise can rapidly increase the frequency and severity of coastal flooding. So far, globalAuthorsSean Vitousek, Patrick L. Barnard, Charles H. Fletcher, Neil Frazer, Li H. Erikson, Curt D. StorlazziA model integrating longshore and cross-shore processes for predicting long-term shoreline response to climate change
We present a shoreline change model for coastal hazard assessment and management planning. The model, CoSMoS-COAST (Coastal One-line Assimilated Simulation Tool), is a transect-based, one-line model that predicts short-term and long-term shoreline response to climate change in the 21st century. The proposed model represents a novel, modular synthesis of process-based models of coastline evolutionAuthorsSean Vitousek, Patrick L. Barnard, Patrick W. Limber, Li H. Erikson, Blake ColeExtreme oceanographic forcing and coastal response due to the 2015–2016 El Niño
The El Niño-Southern Oscillation is the dominant mode of interannual climate variability across the Pacific Ocean basin, with influence on the global climate. The two end members of the cycle, El Niño and La Niña, force anomalous oceanographic conditions and coastal response along the Pacific margin, exposing many heavily populated regions to increased coastal flooding and erosion hazards. HoweverAuthorsPatrick L. Barnard, Daniel J. Hoover, David M. Hubbard, Alexander G. Snyder, Bonnie C. Ludka, Jonathan Allan, George M. Kaminsky, Ruggiero, Timu W. Gallien, Laura Gabel, Diana McCandless, Heather M. Weiner, Nicholas Cohn, Dylan L. Anderson, Katherine A. SerafinA multimodal wave spectrum-based approach for statistical downscaling of local wave climate
Characterization of wave climate by bulk wave parameters is insufficient for many coastal studies, including those focused on assessing coastal hazards and long-term wave climate influences on coastal evolution. This issue is particularly relevant for studies using statistical downscaling of atmospheric fields to local wave conditions, which are often multimodal in large ocean basins (e.g. the PacAuthorsChristie Hegermiller, Jose A. A. Antolinez, Ana C. Rueda, Paula Camus, Jorge Perez, Li H. Erikson, Patrick L. Barnard, Fernando J. MendezSea-level rise and coastal groundwater inundation and shoaling at select sites in California, USA
Study regionThe study region spans coastal California, USA, and focuses on three primary sites: Arcata, Stinson Beach, and Malibu Lagoon.Study focus1 m and 2 m sea-level rise (SLR) projections were used to assess vulnerability to SLR-driven groundwater emergence and shoaling at select low-lying, coastal sites in California. Separate and combined inundation scenarios for SLR and groundwater emergenAuthorsDaniel J. Hoover, Kingsley Odigie, Peter W. Swarzenski, Patrick L. BarnardCoastal vulnerability across the Pacific dominated by El Niño-Southern Oscillation
To predict future coastal hazards, it is important to quantify any links between climate drivers and spatial patterns of coastal change. However, most studies of future coastal vulnerability do not account for the dynamic components of coastal water levels during storms, notably wave-driven processes, storm surges and seasonal water level anomalies, although these components can add metres to wateAuthorsPatrick L. Barnard, Andrew D. Short, Mitchell D. Harley, Kristen D. Splinter, Sean Vitousek, Ian L. Turner, Jonathan Allan, Masayuki Banno, Karin R. Bryan, André Doria, Jeff E. Hansen, Shigeru Kato, Yoshiaki Kuriyama, Evan Randall-Goodwin, Peter Ruggiero, Ian J. Walker, Derek K. HeathfieldDevelopment of the Coastal Storm Modeling System (CoSMoS) for predicting the impact of storms on high-energy, active-margin coasts
The Coastal Storm Modeling System (CoSMoS) applies a predominantly deterministic framework to make detailed predictions (meter scale) of storm-induced coastal flooding, erosion, and cliff failures over large geographic scales (100s of kilometers). CoSMoS was developed for hindcast studies, operational applications (i.e., nowcasts and multiday forecasts), and future climate scenarios (i.e., sea-levAuthorsPatrick L. Barnard, Maarten van Ormondt, Li H. Erikson, Jodi Eshleman, Cheryl J. Hapke, Peter Ruggiero, Peter Adams, Amy C. Foxgrover - News
Below are news stories associated with this project.