Warm ocean waters from the developing El Niño are shifting north along coastlines in the eastern Pacific Ocean. Along the coast of California, these warm waters are interacting with a persistent marine heat wave that recently influenced the development of Hurricane Hilary. The Surface Water and Ocean Topography (SWOT) satellite is able to spot the movement of these warm ocean waters in unprecedented detail.

A collaboration between NASA and the French space agency, CNES (Centre National d’Études Spatiales), SWOT is measuring the height of nearly all water on Earth’s surface, providing one of the most detailed, comprehensive views yet of the planet’s oceans and fresh water lakes and rivers.

Water expands as it warms, so sea levels tend to be higher in places with warmer water. El Niño – a periodic climate phenomenon that can affect weather patterns around the world – is characterized by higher sea levels and warmer-than-average ocean temperatures along the western coast of the Americas. The image above shows sea surface heights off the U.S. West Coast, near the California-Oregon border, in August. Red and orange indicate higher-than-average ocean heights, while blue and green represent lower-than-average heights.

The SWOT science team made the measurements with the Ka-band Radar Interferometer (KaRIn) instrument. With two antennas spread 33 feet (10 meters) apart on a boom, KaRIn produces a pair of data swaths as it circles the globe, bouncing radar pulses off the water’s surface to collect water-height measurements. The visualization combines data from two passes of the SWOT satellite.

“SWOT’s ability to measure sea surface so close to the coast will be invaluable for researchers but also forecasters looking at things like the development and progress of worldwide phenomena like El Niño,” said Ben Hamlington, a sea level researcher at NASA’s Jet Propulsion Laboratory in Southern California.

Watch Latest Water Satellite Unfold Itself in Space

In its September outlook, the U.S. National Oceanic and Atmospheric Administration forecast a greater than 70% chance for a strong El Niño this coming winter. In addition to warmer water, El Niño is also associated with a weakening of the equatorial trade winds. The phenomenon can bring cooler, wetter conditions to the U.S. Southwest and drought to countries in the western Pacific, such as Indonesia and Australia.

More About the Mission

Launched on Dec. 16, 2022, from Vandenberg Space Force Base in central California, SWOT is now in its operations phase, collecting data that will be used for research and other purposes.

SWOT was jointly developed by NASA and CNES, with contributions from the Canadian Space Agency (CSA) and the UK Space Agency. NASA’s Jet Propulsion Laboratory, which is managed for the agency by Caltech in Pasadena, California, leads the U.S. component of the project. For the flight system payload, NASA provided the KaRIn instrument, a GPS science receiver, a laser retroreflector, a two-beam microwave radiometer, and NASA instrument operations. CNES provided the Doppler Orbitography and Radioposition Integrated by Satellite (DORIS) system, the dual frequency Poseidon altimeter (developed by Thales Alenia Space), the KaRIn radio-frequency subsystem (together with Thales Alenia Space and with support from the UK Space Agency), the satellite platform, and ground operations. CSA provided the KaRIn high-power transmitter assembly. NASA provided the launch vehicle and the agency’s Launch Services Program, based at Kennedy Space Center, managed the associated launch services.

To learn more about SWOT, visit:

https://swot.jpl.nasa.gov/

Summer of 2023 was Earth’s hottest since global records began in 1880, according to scientists at NASA’s Goddard Institute of Space Studies (GISS) in New York.

The months of June, July, and August combined were 0.41 degrees Fahrenheit (0.23 degrees Celsius) warmer than any other summer in NASA’s record, and 2.1 degrees F (1.2 C) warmer than the average summer between 1951 and 1980. August alone was 2.2 F (1.2 C) warmer than the average. June through August is considered meteorological summer in the Northern Hemisphere.

This new record comes as exceptional heat swept across much of the world, exacerbating deadly wildfires in Canada and Hawaii, and searing heat waves in South America, Japan, Europe, and the U.S., while likely contributing to severe rainfall in Italy, Greece, and Central Europe.

“Summer 2023’s record-setting temperatures aren’t just a set of numbers – they result in dire real-world consequences. From sweltering temperatures in Arizona and across the country, to wildfires across Canada, and extreme flooding in Europe and Asia, extreme weather is threatening lives and livelihoods around the world,” said NASA Administrator Bill Nelson. “The impacts of climate change are a threat to our planet and future generations, threats that NASA and the Biden-Harris Administration are tackling head on.”

NASA assembles its temperature record, known as GISTEMP, from surface air temperature data acquired by tens of thousands of meteorological stations, as well as sea surface temperature data from ship- and buoy-based instruments. This raw data is analyzed using methods that account for the varied spacing of temperature stations around the globe and for urban heating effects that could skew the calculations.

The analysis calculates temperature anomalies rather than absolute temperature. A temperature anomaly shows how far the temperature has departed from the 1951 to 1980 base average.

“Exceptionally high sea surface temperatures, fueled in part by the return of El Niño, were largely responsible for the summer’s record warmth,” said Josh Willis, climate scientist and oceanographer at NASA’s Jet Propulsion Laboratory in Southern California.

El Niño is a natural climate phenomenon characterized by warmer than normal sea surface temperatures (and higher sea levels) in the central and eastern tropical Pacific Ocean.

The record-setting summer of 2023 continues a long-term trend of warming. Scientific observations and analyses made over decades by NASA, National Oceanic and Atmospheric Administration (NOAA), and other international institutions have shown this warming has been driven primarily by human-caused greenhouse gas emissions. At the same time, natural El Niño events in the Pacific pump extra warmth into the global atmosphere and often correlate with the warmest years on record.

“With background warming and marine heat waves that have been creeping up on us for decades, this El Niño shot us over the hump for setting all kinds of records,” Willis said. “The heat waves that we experience now are longer, they’re hotter, and they’re more punishing. The atmosphere can also hold more water now, and when it’s hot and humid, it’s even harder for the human body to regulate its temperature.”

Willis and other scientists expect to see the biggest impacts of El Niño in February, March, and April 2024. El Niño is associated with the weakening of easterly trade winds and the movement of warm water from the western Pacific toward the western coast of the Americas. The phenomenon can have widespread effects, often bringing cooler, wetter conditions to the U.S. Southwest and drought to countries in the western Pacific, such as Indonesia and Australia.

“Unfortunately, climate change is happening. Things that we said would come to pass are coming to pass,” said Gavin Schmidt, climate scientist and director of GISS. “And it will get worse if we continue to emit carbon dioxide and other greenhouse gases into our atmosphere.”

NASA’s full temperature data set and the complete methodology used for the temperature calculation and its uncertainties are available online.

GISS is a NASA laboratory managed by the Earth Sciences Division of the agency’s Goddard Space Flight Center in Greenbelt, Maryland. The laboratory is affiliated with Columbia University’s Earth Institute and School of Engineering and Applied Science in New York.

For additional figures and maps related to this announcement, visit:

https://svs.gsfc.nasa.gov/14407

News Media Contacts

Karen Fox/Aries Keck
Headquarters, Washington
202-358-1100
karen.fox@nasa.gov/aries.keck@nasa.gov

Jacob Richmond
Goddard Space Flight Center
301-286-6255
jacob.a.richmond@nasa.gov

A state-of-the-art imaging spectrometer, which will measure the greenhouse gases methane and carbon dioxide from space, moved closer to launch this month after being delivered to a clean room at Planet Labs PBC (Planet) in San Francisco.

Designed and built by NASA’s Jet Propulsion Laboratory in Southern California, this science instrument will be part of an effort led by the nonprofit Carbon Mapper organization to collect data on greenhouse gas point-source emissions. Built around technologies developed for NASA airborne campaigns and space missions, the Carbon Mapper imaging spectrometer will provide targeted data on “super-emitters” – the small percentage of individual sources responsible for a significant fraction of global methane and carbon dioxide emissions.

The Carbon Mapper coalition is a public-private effort led by the Carbon Mapper organization and its partners, including JPL, Planet, the California Air Resources Board, Rocky Mountain Institute, Arizona State University, and the University of Arizona.

The instrument is an advanced imaging spectrometer that measures hundreds of wavelengths of light reflected by Earth’s surface and absorbed by gases in the planet’s atmosphere. Different compounds – including methane and carbon dioxide – absorb different wavelengths of light, leaving a spectral “fingerprint” that the imaging spectrometer can identify. These infrared fingerprints, invisible to the human eye, can pinpoint and quantify strong greenhouse gas emissions and accelerate potential mitigation efforts.

The spectrometer arrived Sept. 12 at Planet, where it will be integrated over the next several months into a Tanager satellite designed by the company. Launch is planned for early 2024.

Before leaving JPL, the spectrometer was put through a series of critical tests to ensure that it could withstand the rigors of launch and the harsh conditions of space. Engineers subjected the spectrometer to intense vibrations similar to what it will endure atop a rocket blasting into orbit, as well as to the extreme temperatures it will experience in the vacuum of space.

There was also an opportunity to use a sample of methane to test the completed instrument while it was in a vacuum chamber at JPL. The test was successful, with the imaging spectrometer producing a clear spectral fingerprint of methane.

“We are thrilled to see the exceptional quality of the methane spectral signature recorded. This bodes well for the space measurement soon to follow,” said Robert Green, the instrument scientist at JPL.

“This delivery is a very exciting step for us as our team can now begin the final stage in satellite integration,” said Jeff Guido, senior director of new missions at Planet. “This milestone is an excellent example of the innovative ways that government, philanthropy, and industry can play to each other’s strengths to build exceptional capability that has the potential for global impact.”

The new satellite is part of a broader effort by Carbon Mapper to survey the globe for point-source emissions of methane and carbon dioxide. That effort includes using measurements provided by an instrument already in orbit: NASA’s Earth Surface Mineral Dust Source Investigation, or EMIT, an imaging spectrometer developed by JPL and installed on the International Space Station. A second imaging spectrometer is being built by Planet in collaboration with JPL. The teams will continue working side by side to deliver these new greenhouse gas measurement capabilities.

More About the Project

Carbon Mapper is a nonprofit organization focused on facilitating timely action to mitigate greenhouse gas emissions. Its mission is to fill gaps in the emerging global ecosystem of methane and carbon dioxide monitoring systems by delivering data at facility scale that is precise, timely, and accessible to empower science-based decision making and action. The organization is leading the development of the Carbon Mapper constellation of satellites supported by a public-private partnership composed of Planet Labs PBC, JPL, the California Air Resources Board, the University of Arizona, Arizona State University, and RMI, with funding from High Tide Foundation, Bloomberg Philanthropies, Grantham Foundation for the Protection of the Environment, and other philanthropic donors.

News Media Contact

Jane J. Lee / Andrew Wang
Jet Propulsion Laboratory, Pasadena, Calif.
818-354-0307 / 626-379-6874
jane.j.lee@jpl.nasa.gov / andrew.wang@jpl.nasa.gov

Kelly Vaughn
Carbon Mapper, Pasadena, Calif.
970-401-0001
kelly@carbonmapper.org

Like much of the planet, Southern California is expected to experience more heat waves in the future due to Earth’s changing climate. And some of these will feel increasingly humid, as long-term forecasts call for muggy spells more typically associated with Florida or eastern Texas.

To begin to understand what these changes could mean across the greater Los Angeles area, scientists at NASA’s Jet Propulsion Laboratory in Southern California mapped how extreme heat and humidity patterns vary with regional geography. The results underscore how air temperature alone does not tell the full story of dangerous heat.

“We can’t just look at air temperature when we talk about heat wave impacts,” said study author Anamika Shreevastava, a NASA postdoctoral program fellow at JPL. “People tend to get acclimatized to where they live. We have to understand how anomalous conditions are making a difference in what people are used to.”

Climate change is fueling longer, hotter, and more frequent heat waves. In the U.S., extreme heat is the No. 1 weather-related killer, causing more deaths than hurricanes and floods, according to the National Weather Service.

Greater Los Angeles is a prime example of an urban heat island – cities and suburbs woven with heat-trapping concrete and asphalt that lead to warmer temperatures than nearby rural areas that have more vegetation. Bordered by mountains and the ocean, the Greater L.A. area encompasses suburbs and skyscrapers, with a dense population and disparities in green space. It includes several counties, tens of thousands of square miles, and more than 18 million people, making it a compelling test bed for heat wave research.

Climate change and urban heat are together fueling different heat waves now. In the 20th century, most heat waves in L.A. were dry. However, humid events have steadily increased in frequency and intensity since 1950 due in part to swelling moisture from the warming sea surface.

In their case study, JPL scientists compared two heat waves that affected the Greater Los Angeles area in the summer of 2020: a prolonged muggy stretch in August and an extremely dry three-day spike in September. During the latter event, record-breaking temperatures soared over 120 degrees Fahrenheit (49 degrees Celsius) in the San Fernando Valley – a densely populated portion of the city of Los Angeles – while scorching winds fanned a destructive wildfire in the nearby San Gabriel Mountains.

For their study, recently published in the Journal of Applied Meteorology and Climatology, the scientists used NASA’s Modern-Era Retrospective Analysis for Research and Applications, version 2 (MERRA-2) data set – a reanalysis of historical atmospheric observations. They found that both heat waves drove temperatures above the 90th percentile for the August-September climate record in L.A. Using advanced weather modeling, they simulated the heat waves and looked at their impacts across the region.

The researchers found that, although air temperatures were as much as 18 degrees Fahrenheit (10 degrees Celsius) cooler during the muggy August heat wave, the heat stress to human health was more intense than the September event. That’s because the wet-bulb temperature – which relates heat to how well our bodies cool down by sweating – surged due to the humidity.

The results underscore the importance of including humid heat when issuing extreme heat warnings, the scientists said.

Local Impacts

Another key finding of the study was that heat waves don’t touch every place the same way. “The same heat wave can feel different because of local climate variabilities and disparities in vegetation, which has a shading and cooling effect. These small-scale variabilities make a big difference in impact,” said Shreevastava, who studies extreme heat and its effect on urban and natural ecosystems.

Shreevastava and her team examined three regions that experienced the 2020 heat waves differently: Southern L.A. County and Orange County stayed cooler, given their proximity to the Pacific Ocean and coastal moisture. Valley regions, including San Fernando and Riverside, skewed drier and hotter. And central L.A. fell between the two extremes.

Despite the microclimate variations, humidity had a leveling effect: Both the coastal and inland areas experienced increased nighttime heat stress during the muggy August heat wave. This was a notable change for the valley regions, which historically have countered scorching daytime temperatures with drier nights. Valley areas such as those in San Bernardino and Riverside counties experienced the greatest change over recent historical averages, with up to 10.8 degrees Fahrenheit (6 degrees Celsius) of added heat stress during humid heat wave nights.

The researchers said that their findings highlight how disparities in small-scale heat wave patterns across urban neighborhoods are vitally important when designing emergency plans and policies for our shared, hotter future.

News Media Contacts

Jane J. Lee / Andrew Wang
Jet Propulsion Laboratory, Pasadena, Calif.
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jane.j.lee@jpl.nasa.gov / andrew.wang@jpl.nasa.gov

Editor's Note: This release has been updated to add additional graphics, captions, and to spell out the words degrees Fahrenheit and Celsius.

According to scientists at NASA’s Goddard Institute for Space Studies (GISS) in New York, July 2023 was hotter than any other month in the global temperature record.

“Since day one, President Biden has treated the climate crisis as the existential threat of our time,” said Ali Zaidi, White House National Climate Advisor. Against the backdrop of record high temperatures, wildfires, and floods, NASA’s analysis puts into context the urgency of President Biden’s unprecedented climate leadership. From securing the Inflation Reduction Act, the largest climate investment in history, to invoking the Defense Production Act to supercharge domestic clean energy manufacturing, to strengthening climate resilience in communities nationwide, President Biden is delivering on the most ambitious climate agenda in history.”

Overall, July 2023 was 0.43 degrees Fahrenheit (F) (0.24 degrees Celsius (C)) warmer than any other July in NASA’s record, and it was 2.1 F (1.18 C) warmer than the average July between 1951 and 1980. The primary focus of the GISS analysis are long-term temperature changes over many decades and centuries, and a fixed base period yields anomalies that are consistent over time. Temperature "normals" are defined by several decades or more - typically 30 years.

“NASA data confirms what billions around the world literally felt: temperatures in July 2023 made it the hottest month on record. In every corner of the country, Americans are right now experiencing firsthand the effects of the climate crisis, underscoring the urgency of President Biden’s historic climate agenda,” said NASA Administrator Bill Nelson. “The science is clear. We must act now to protect our communities and planet; it’s the only one we have.”

Parts of South America, North Africa, North America, and the Antarctic Peninsula were especially hot, experiencing temperatures increases around 7.2 F (4 C) above average. Overall, extreme heat this summer put tens of millions of people under heat warnings and was linked to hundreds of heat-related illnesses and deaths. The record-breaking July continues a long-term trend of human-driven warming driven primarily by greenhouse gas emissions that has become evident over the past four decades. According to NASA data, the five hottest Julys since 1880 have all happened in the past five years.

“Climate change is impacting people and ecosystems around the world, and we expect many of these impacts to escalate with continued warming,” said Katherine Calvin, chief scientist and senior climate advisor at NASA Headquarters in Washington. “Our agency observes climate change, its impacts, and its drivers, like greenhouse gases, and we are committed providing this information to help people plan for the future.”

NASA assembles its temperature record from surface air temperature data from tens of thousands of metrological stations, as well as sea surface temperature data acquired by ship- and buoy-based instruments. This raw data is analyzed using methods that account for the varied spacing of temperature stations around the globe and for urban heating effects that could skew the calculations.

“This July was not just warmer than any previous July – it was the warmest month in our record, which goes back to 1880,” said GISS Director Gavin Schmidt. “The science is clear this isn’t normal. Alarming warming around the world is driven primarily by human-caused greenhouse gas emissions. And that rise in average temperatures is fueling dangerous extreme heat that people are experiencing here at home and worldwide.”

High sea surface temperatures contributed to July’s record warmth. NASA’s analysis shows especially warm ocean temperatures in the eastern tropical Pacific, evidence of the El Niño that began developing in May 2023. Phenomena such as El Niño or La Niña, which warm or cool the tropical Pacific Ocean, can contribute a small amount of year-to-year variability in global temperatures. But these contributions are not typically felt when El Niño starts developing in Northern Hemisphere summer. NASA expects to see the biggest impacts of El Niño in February, March, and April 2024.

For more information on NASA’s global temperature record, visit:

https://www.nasa.gov/feature/2023/climate-media-resources

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