What's New Archive
Rainfall declines may affect U.S. West Coast and parts of the East Coast
New research by NOAA and a visiting scientist from India shows that warming of the Indo-Pacific Ocean is altering rainfall patterns from the tropics to the United States, contributing to declines in rainfall on the United States west and east coasts.
In a study published this week in the journal Nature, researchers report a doubling in the size of a warm pool of water spanning the western Pacific and eastern Indian Ocean in recent years. This Indo-Pacific warm pool in what is already the warmest part of the global ocean is expanding each year by an area the size of California.
The expansion is changing a key weather and climate feature called the Madden Julian Oscillation, which is characterized by a band of rain clouds that move over the tropical ocean from the Seychelles off Africa toward India and into the Pacific Ocean, influencing everything from monsoons in India to heat waves and flooding in the United States.
Warming ocean driving change in key climate pattern
The changes in the behavior of the MJO have brought a decline in rainfall to the central Pacific, the west and east coasts of the United States, north India, east Africa and the Yangtze basin in China. These same changes are causing an increase in rainfall over northern Australia, the Amazon basin, southwest Africa and Southeast Asia, researchers conclude.
“NOAA is part of coordinated international efforts to extend the range of accurate weather forecasts out to lead times of two to four weeks and the MJO is one of the most important keys to the success of this enterprise,” said Michael McPhaden, a senior scientist at NOAA’s Pacific Marine Environmental Lab and co-author of the study. “Our research provides a critical benchmark for determining which computer models to trust for extended range weather forecasting, based on their ability to simulate the observed behavior of the MJO in changing the climate.”
Though the entire Indo-Pacific Ocean has warmed, the warmest waters are over the west Pacific, creating a temperature contrast that drives moisture from the Indian Ocean to the west, enhancing cloud formation. This has changed the life cycle of the MJO. The length of time these clouds linger over the Indian Ocean has shrunk by four days from an average of 19 to 15 days. Over the west Pacific, the clouds now reside five more days. It is this change in the residence of MJO-driven clouds that is altering weather patterns around the globe, researchers found.
“Climate model simulations indicate that continued warming of the Indo-Pacific Ocean is highly likely, which may further intensify these changes in global rainfall patterns,” said Roxy Mathew Koll, lead author of the study with the Indian Institute of Tropical Meteorology who worked with McPhaden while visiting PMEL for the last year. “This means that we need to enhance our ocean observational arrays to monitor these changes accurately, and update our climate models to skillfully predict the challenges presented by a warming world.”
The study is part of a collaboration between NOAA and India’s Ministry of Earth Sciences, facilitated by the National Academy of Sciences with funding from NOAA’s Climate Program Office Climate Variability and Predictability Program. In addition to McPhaden, Chidong Zhang, also of NOAA PMEL, is a co-author of the research.
Originally posted on NOAA Research on November 27, 2019.
Dr. Patricia Quinn of NOAA’s Pacific Marine Environmental Laboratory has been named a Fellow of the American Association for the Advancement of Science (AAAS). Election as a AAAS Fellow is an honor bestowed upon AAAS members by their peers. This year 443 members have been awarded this honor by AAAS because of their scientifically or socially distinguished efforts to advance science or its applications.
As part of the Atmospheric and Hydrospheric Sciences Section, Dr. Quinn was elected as an AAAS Fellow for her exceptional scientific contributions to our understanding of atmospheric aerosols and their climate impact.
Dr. Quinn has been with PMEL for over 25 years and is currently the lead for the Atmospheric Chemistry group studying the effects of atmospheric aerosol particles on air quality and climate. She has participated in research cruises since 1986, studying a broad range of aerosol types ranging from remote marine aerosol in the Arctic and Antarctic to pollution aerosol in the Houston Ship Channel and the oil and gas fields of Utah’s Uintah Basin.
Dr. Quinn has also been recognized as a highly cited researcher in Web of Science (2016, 2017, and 2018) and selected as an AGU Fellow in 2010.
Read the full announcement in the AAAS News and Notes section of the journal Science on 29 November 2019.
NOAA and Oregon State University researchers have developed an effective method to use an underwater robotic glider to measure sound levels over broad areas of the ocean, published today in the journal PLOS ONE.
“Healthy marine ecosystems need to have noise levels within particular ranges,” said Joe Haxel, lead author of the paper and assistant professor/senior research at Oregon State University and part of NOAA’s Pacific Marine Environmental Lab Acoustics Program. “As an analogy for humans it’s the difference between living in the country or living in the city or somewhere really loud.”
Ocean sound was recently listed as an essential ocean variable by the Global Ocean Observing System, a UNESCO program, due to its importance for marine life and seagoing humans and because it is used to monitor and locate everything from earthquakes to tsunamis to nuclear explosions.
Traditionally, scientists have measured ocean sound by attaching hydrophones, essentially an underwater microphone, to a fixed mooring in the water. The problem with that is scientists only get data from that single location. Ocean sound can also be measured from a research ship, but they are expensive to operate. They also create a lot of noise themselves, which disturbs marine animals and fish that are sensitive to sound.
Attaching a hydrophone to a glider solves those problems because gliders operate autonomously, relatively quietly and can cover hundreds of miles over several weeks.
Gliders equipped with hydrophones can conduct repeated surveys of a region of concern for acoustic habitat degradation and provide real-time measurements of changing noise levels. Gliders have also successfully been used by scientists to measure noise from an underwater volcano and to predict surface wind speeds. An additional benefit of gliders is that they are outfitted with other sensors and instruments that provide important measurements, such as temperature, salinity and depth.
In the research described in the PLOS ONE paper, the research team attached the hydrophone to the glider, which is about 5 feet long and weighs about 120 pounds. The glider traveled for 18 days between Grey’s Harbor, Washington and Brookings, Oregon, a distance of about 285 miles. The glider operated along the North American continental shelf break, which on average is about 30 miles off the coast where the ocean depth begins to drop more steeply. The shelf break is a key migratory path for marine animals.
Once the scientists retrieved the hydrophone data, their main challenge was fine-tuning their algorithms to filter out the noise the glider creates when operating. After that filtering occurred, the researchers were able to cross-reference the data collected during the 18-day glider trip with historical data from hydrophones attached to moorings along that route.
Haxel said it was pretty shocking how closely the data sets aligned. That led the team to conclude that the gliders are an effective and valuable asset for measuring underwater ocean sound.
Read the paper here: https://doi.org/10.1371/journal.pone.0225325
The story was originally published by Oregon State University on November 20, 2019.
A new report details the effects of a changing climate on Puget Sound in 2018, and describes how these changes trickled down through the ecosystem to affect marine life and seafood consumers. Since 2011, Puget Sound Marine Waters has compiled data from numerous environmental monitoring programs to report on the state of Puget Sound’s marine waters during the previous year.
In 2018, Puget Sound witnessed the effects of a changing climate. Total annual rainfall was near normal for 2018, but the Puget Sound experienced a wetter than normal spring, followed by a record-setting summer drought. These conditions resulted in waters that were warmer and saltier than past averages and had lower oxygen levels. Scientists observed unusually warm water temperatures, though not as hot as during the years of “the Blob,” the marine heatwave of 2014-2016. Salinity went up everywhere in the Puget Sound through the summer and fall, in response to the record-setting summer drought. Hypoxia (a lack of oxygen) was more apparent in 2018 than previous years, though no fish kills were reported. Scientists reported lower numbers of fish, seabirds, and marine mammals, including continuing declines in endangered Southern Resident killer whales.
Atmospheric carbon dioxide (CO2) measured off the coast and in Puget Sound continued its annual increase, with coastal values near the global average and Puget Sound values in excess. In stratified basins, CO2 concentrations in surface seawater are quite different from those measured at depth. Levels potentially conducive to hypercapnia (harmfully high CO2) were present in the deep waters of Whidbey Basin and Hood Canal during 2018. Atmospheric measurements of the mole fraction of carbon dioxide (xCO2) at the Ćháʔba· and Cape Elizabeth moorings on the Washington shelf continued their year-to-year increases in 2018, and were similar to the global averages. The summertime minimum was earlier at Cape Elizabeth in 2018 relative to other years. 2018 surface seawater xCO2 values at Ćháʔba· and Cape Elizabeth were within the range of past years.
The Puget Sound Ecosystem Monitoring Program’s Marine Waters Work Group, who authored the report, has been tracking the health of Puget Sound since 2011. This work group includes scientists from federal, tribal, state and local agencies, academia, nonprofits, and private and volunteer groups.
The work group looked at several environmental indicators, including plankton, water quality, climate, and marine life, that, when considered together, provide both a long-term view and current assessment of the Sound’s health.
A mosaic of young sea ice captured during a flight campaign over the Chukchi Sea launching various atmospheric and oceanographic probes and floats.
The black dots show the observed day of year that sea-ice concentration in the reference area northwest of Icy Cape first reaches 30%, as determined from passive microwave data. The blue markers show the range (14 days) of the projected onset of freeze in 2019. The dashed line shows the long-term mean (1981-2016).
PMEL has released an experimental annual freeze-up projection for the Chukchi Sea continental shelf northwest of Icy Cape. The freeze onset is projected to begin between 23 November and 6 December 2019. This is 28-41 days later than the long-term average (1981-2016). At freeze-up in 2019, sea-ice in the northwest of Icy Cape will consist entirely of thin, newly formed types (e.g. sheets and thin pancake), especially near the coast. For this projection, the onset metric is defined by sea-ice concentration reaching 30% as determined by passive microwave observations collected in the area around Icy Cape in the Chukchi Sea.
The data considered in this projection includes observations collected from autonomous ocean profiling floats, aircraft and satellite-derived visible imagery, and SST radiometry in 2016, 2017, 2018 and 2019. Persistence of sea ice was evaluated using historical ice concentration data from passive microwave satellites, provided by the National Snow and Ice Data Center (NSIDC).
The purpose of this experiment is to develop an informed basis for advising a hypothetical maritime interest operating in the region and to identify conditions that cause sudden large departures (increase in risk). It also provides a result that can be evaluated against other methodologies. Data from various technologies deployed during the Arctic Heat flight campaigns help to fill in data gaps in the Arctic and determine limiting factors in projecting sea ice freeze up in hopes of improving seasonal model forecasts.
Read the full projection and rationale here: https://www.pmel.noaa.gov/arctic-heat/projected-onset-freeze-chukchi-sea-continental-shelf-2019
Learn more about the work being done on the Arctic Heat page: https://www.pmel.noaa.
At the end of September, PMEL and partners aboard the Kaiyo Maru #1 successfully completed the Kuroshio Extension Observatory (KEO) mooring turnaround cruise during typhoon season. Although the cruise faced delays due to typhoon Tapah, the KEO mooring was both deployed and recovered successfully in a single 24-hour period, and was ready to observe Super Typhoon Hagibis, which made landfall on October 12. In addition to the mooring, four JAMSTEC backscatters meters and an underwater camera were deployed.
KEO continues to demonstrate its dual-purpose of relaying real-time weather information and contributing to longer climatological records. The KEO mooring is also known as a storm mooring due to its prime location to observe the transition of tropical cyclones to extra-tropical storms and measure the exchanges of heat and moisture between the atmosphere and ocean during these storms. Partners such as the Japan Agency for Marine-Earth Science and Technology (JAMSTEC) use the KEO mooring site to conduct their own research and enhance the mooring with additional sensors.
Typhoons are common in the western North Pacific in the summer and fall. On average, a typhoon passes within 500 nautical miles of the KEO mooring every two weeks during the peak of the tropical cyclone season. Data from ocean climate stations moorings can be used to help improve weather and storm forecasts, inform climate projections, and verify satellite products and models. The Kuroshio Extension current carries warm water into the North Pacific and is a region where the ocean generally loses heat to the atmosphere. The exchange of heat and moisture into the atmosphere is an important factor in the development of storms over the north Pacific before they reach the United States.
Storms, boat traffic, animal noises and more contribute to the underwater sound environment in the ocean, even in areas considered protected, a new study from Oregon State University, Cornelle University, National Park Service, and NOAA PMEL and NOAA Fisheries scientists shows.
Using underwater acoustic monitors, researchers listened in on Stellwagen Bank National Marine Sanctuary off the coast of Boston; Glacier Bay National Park and Preserve in Alaska; National Park of American Samoa; and Buck Island Reef National Monument in the Virgin Islands. They found that the ambient sounds varied widely across the sites and were driven by differences in animal vocalization rates, human activity and weather.
The findings demonstrate that sound monitoring is an effective tool for assessing conditions and monitoring changes, said Samara Haver, a doctoral candidate in the College of Agricultural Sciences at OSU and the study’s lead author. “This is a relatively economical way for us to get a ton of information about the environment,” said Haver, who studies marine acoustics and works out of the Cooperative Institute for Marine Resources Studies, a partnership between OSU and the National Oceanic and Atmospheric Administration at the Hatfield Marine Science Center in Newport. “Documenting current and potentially changing conditions in the ocean soundscape can provide important information for managing the ocean environment.”
Passive acoustic monitoring is seen as a cost-effective and low-impact method for monitoring the marine environment. The researchers’ goal was to test how effective acoustic monitoring would be for long-term assessment of underwater conditions.
“Ocean noise levels have been identified as a potential measure for effectiveness of conservation efforts, but until now comparing sound across different locations has been challenging,” Haver said. “Using equipment that was calibrated across all of the sites, we were able to compare the sound environments of these diverse areas in the ocean.”
The researchers collected low frequency, passive acoustic recordings from each of the locations between 2014 and 2018. They compared ambient sounds as well as sounds of humpback whales, a species commonly found in all four locations. The inclusion of the humpback whale sounds – mostly songs associated with mating in the southern waters, and feeding or social calls in the northern waters – gives researchers a way to compare the sounds of biological resources across all the soundscapes, Haver said.
The researchers found that ambient sound levels varied across all four study sites and sound levels were driven by differences in animal vocalization rates, human activity and weather. The highest sound levels were found in Stellwagen Bank during the winter/spring, driven by higher animal sound rates, vessel activity and high wind speeds. The lowest sound levels were found in Glacier Bay in the summer.
“Generally, the Atlantic areas were louder, especially around Stellwagen, than the Pacific sites,” Haver said. “That makes sense, as there is generally more man-made sound activity in the Atlantic. There also was a lot of vessel noise in the Caribbean.”
The researchers also were able to hear how sound in the ocean changes before, during and after hurricanes and other severe storms; the monitoring equipment captured Hurricanes Maria and Irma in the Virgin Islands and Tropical Cyclone Winston in American Samoa. Ultimately, the study provides a baseline for these four regions and can be used for comparison over time. Documenting current and potentially changing conditions in the ocean soundscape can provide important information for managing the ocean environment, particularly in and around areas that have been designated as protected, Haver said.
This story was originally posted by Oregon State University: https://today.oregonstate.edu/news/underwater-soundscapes-reveal-differences-marine-environments
Learn more about PMEL's work with NOAA and National Park Service's Noise Reference Station here: https://www.pmel.noaa.gov/acoustics/noaanps-ocean-noise-reference-station-network
It was an audacious idea: To send an unmanned saildrone on a 13,670-mile journey around Antarctica alone, at the mercy of the most hostile seas on the planet. In winter.
“The assumption was the Southern Ocean would eat the saildrone … and that would be that,” said NOAA oceanographer Adrienne Sutton. “But we were willing to try, given the large role the ocean plays in the trajectory of climate change. Getting the Southern Ocean's carbon balance right is urgently important."
Despite a run-in with an iceberg that wrecked some of its sensors, Saildrone 1020 completed its mission on August 3 having successfully collected oceanic and atmospheric carbon dioxide measurements with an instrument developed by NOAA’s Pacific Marine Environmental Laboratory.
The 196-day voyage was the world’s first autonomous circumnavigation of Antarctica — a technological feat that was unfathomable just a decade ago.
An arduous journey around the end of the world
Saildrone 1020 and two counterparts launched from Point Bluff, New Zealand on January 19, 2019, on a mission funded by the Li Ka Shing Foundation. The three saildrones collect and transmit a range of data on weather, seal and krill populations, and levels of carbon dioxide, CO2, in the air and water.
Until recently, scientists assumed that the Southern Ocean steadily absorbed large volumes of CO2 from the atmosphere — a big contributor to the entire ocean’s uptake of up to 40 percent of the greenhouse gases driving global warming.
However, scientists also knew shifts in winds and circulation around Antarctica could alter CO2 uptake from the atmosphere, and recent measurements from instrumented Argo floats showed that under certain conditions the Southern Ocean could emit CO2 instead of absorbing it. But researchers had yet to sample vast areas, especially during stormy autumn and winter seasons.
The severe weather survived by the saildrone demonstrated why.
Pounded by storms right after leaving New Zealand, Saildrone 1020’s partners, Saildrones 1022 and 1023, were soon forced to return to port for repairs, while Saildrone 1020 pushed on through roaring winds and giant waves.
Navigating east of the Drake Passage on April 5, a collision with an iceberg damaged its atmospheric sensors and onboard camera, but left the carbon dioxide sensor intact.
“On four previous voyages in the Southern Ocean, the wings on our saildrones broke after just a few days, so we went back and built something we thought was indestructible,” said Saildrone founder and CEO Richard Jenkins. “It was a long shot, but it worked out exactly as we hoped."
Preliminary results suggest that parts of the ocean identified by the floats as potential CO2 sources were indeed emitting the greenhouse gas during winter months. Saildrone 1020 also got close enough to one of the floats to allow scientists to compare their CO2 measurements, a valuable cross-check of different robots and observing techniques.
“It was a high-risk, high reward kind of deployment,” Sutton said. “We weren’t sure it was going to make it.
Meanwhile, after being repaired and relaunched, Saildrones 1022 and 1023 are finding their own their way around Antarctica now.
PMEL is excited to host seven undergraduates this summer from across the United States! They are working across various research groups studying ocean carbon, Madden-Julian oscillation impacts, meteorological data from Station Papa, fisheries-oceanography research in the Bering Sea, acoustic data from the Ross Sea, and analyzing e-DNA samples. The students are supported through NOAA, University of Washington’s Joint Institute for the Study of the Atmosphere and Ocean (JISAO) internship program, and Oregon State University’s Research Experience for Undergraduates.
Harrison Knapp is a NOAA Hollings Scholar working with Dr. Chidong Zhang on assessing the influence of the Madden-Julian Oscillation on snowpack in the Western United States. He is currently a student at the University of Southern California pursuing both a B.S. in GeoDesign and a B.A. in Earth Sciences.
Sam Mogen is a NOAA Hollings Scholar working with Drs. Jessica Cross and Darren Pilcher on exploring oxygen cycling in the Bering Sea using the Bering 10K model. He is a student at the University of Virginia studying environmental science and global studies.
Madeline Talebi is a JISAO intern working with Drs. Meghan Cronin and Nick Bond on finding and interpreting archived meteorological data from Station Papa Ocean Weather Ship between December 1949 and 1981. She is currently studying Chemical Engineering at the University of California, Irvine.
Isabelle Chan is a JISAO intern working on decreasing the degree of uncertainty between water vapor and carbon dioxide measurements with Dr. Sophie Chu. She is currently studying Environmental Science with an emphasis in Conservation at the University of North Carolina, Wilmington.
Leo MacLeod is a undergraduate at the University of Washington working with Dr. Carol Ladd on fisheries-oceanography research in the Bering Sea.
Ellie Lee is a JISAO intern working with Dr. Carol Stepien in the Genetics and Genomics Group.
Miriam Hauer-Jense is working with Drs. Bob Dziak and Joe Haxel on analyzing data from the Ross Sea hydrophones for marine mammals through Oregon State University’ Research Experience for Undergraduates program. She is a sophomore at Scripps College.
Read more about each of them and their projects here.
On May 16, six saildrones loaded with scientific instruments and cameras launched from a dock in Alaska's Dutch Harbor to monitor ongoing changes to the U.S. Arctic ecosystem food-chain, ice movement, and large-scale climate and weather systems.
This is the first year NOAA and NASA scientists will be working together to use the drones to survey as close to the Arctic ice edge as possible. Measurements collected this summer in the Arctic will not only be used to improve NOAA and NASA satellite ocean temperature measurements, they will also be available to global weather agencies for operational use.
While most of the saildrones will be pursuing the ice edge for the duration of the three-month mission, two other simultaneous projects will also tackle some big questions on how this cutting-edge technology can be used to collect critical observations. NOAA PMEL scientists will continue to study how the Chukchi Sea is absorbing carbon dioxide to help improve weather and climate forecasting as well as our understanding of ongoing changes in the Pacific-Arctic ecosystem. The Bering Sea is home to the largest walleye pollock fishery and the declining population of northern fur seal which primarily feed on pollock. During the summer, NOAA Fisheries scientists will use the saildrone combined with traditional at-sea tracking techniques and video cameras to get a seals-eye view during fur seal feeding trips and measure walleye pollock abundance and distribution. Read more about the work done by NOAA's Alaska Fisheries Science Center.
This is a joint NOAA mission along with the Earth & Space Research, the University of Washington's Joint Institute for the Study of Ocean and Atmosphere and the Applied Physics Lab, and Saildrone, Inc.
Saildrones have traveled about 45,000 nautical miles on Arctic missions since 2015. Follow along with drones as they collect data on fish, fur seals, changes in the Arctic ecosystem and more on the mission blog.