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Astronaut Matthew Dominick captured this dramatic image of Hurricane Beryl from the International Space Station on July 1, 2024. At the time, the cyclone's winds were howling at 150 miles per hour. Beryl was the earliest Atlantic basin Category-5 hurricane on record and the strongest June and July hurricane in the basin. The hurricane roared across parts of the Caribbean and the Yucatn Peninsula, making landfall in the United States along the Gulf Coast as a Category-1 storm. (Credit: NASA)NewsletterSign up for our email newsletter for the latest science newsWhen I conceived the idea for this column in 2013, I came up with the name "ImaGeo" as a mashup of "image" and "geo" as in "images of Earth." (The mashup also hinted at "imagination.")Since then, I've tried whenever possible to emphasize images of Earth from space, as well as imagery created with data from other kinds of sensors. With that original ImaGeo theme in mind as 2024 was drawing to a close, I thought I would pick a selection of compelling images that helped me tell the stories of noteworthy events during the year just ending. This is the first of a two-part series featuring these images. It covers events running through spring. Part 2, will pick things up in summer and take us through the fall and into the winter. Volcanic ExuberanceAlthough there are no signs that volcanic activity is increasing globally, it was nonetheless quite a spectacular year for eruptions. As of Dec. 23, there were 72 confirmed eruptions during 2024 from 64 different volcanoes, of which 30 were new, according to the Global Volcanism Program of the Smithsonian Institution. Iceland's Reykjanes Peninsula has seen its share of this activity. It cracked open in December of 2023, commencing a series of eruptions that still continues. At the start of 2024, burning lava poured across a bright, snow-covered landscape, making for a dramatic view from space as seen in this image from a Copernicus Sentinel 2 satellite:The heat signature from lava erupting on Iceland's Reykjanes Peninsula is seen in this image captured by one of the Copernicus Sentinel-2 satellites on Feb. 8, 2024, less than 10 hours after the event began. (Credit: European Union, Copernicus Sentinel-2 imagery)As I wrote in a story published Feb. 13, land around the world famous Blue Lagoon and the nearby Svartsengi geothermal power plant was rising at a rate of about 0.5 to 1.0 centimeters per day. "Magma thus continues to accumulate in the magma reservoir beneath Svartsengi," stated an update from the Icelandic Met Office at the time. "It is therefore highly likely that the cycle continues in a few weeks with another dyke propagation and a volcanic eruption."Volcanic activity there has indeed continued, and in November, lava encroached on the Blue Lagoon. This new activity also was captured in remote sensing imagery which I'll feature in Part 2 of this series, as a kind of bookend. El Nio Bids Adieu, But Where in the World is La Nia?The El Nio of 1993 and 1994 was a doozy. Considered a strong episode, the natural climate phenomenon contributed to an unprecedented streak of 15 straight months of global heating records. Characterized by warmer than normal sea surface temperatures along the equator in the Pacific Ocean, and implicated in a host of extreme weather impacts, the El Nio finally petered out in May of 2024. Its demise was heralded by a gargantuan blob of relatively cool water rising from the depths of the ocean. You can see it in this animation showing the evolution of sea temperatures in a 1,000 foot cross section of the Pacific Ocean along the Equator from December of 2023 through January of 2024: Water temperatures between December 2023 and January 2024 in the top 300 meters (1,000 feet) of the tropical Pacific Ocean, compared to the 19912020 average. (Credit: NOAA Climate.gov animation, based on data from NOAA's Climate Prediction Center.)The warm colors show El Nio's characteristic abnormal warmth at and near the surface in the central and eastern equatorial Pacific. But at that same time, a chilly phantom was rising from the depths and spreading eastward, threatening to replace the warm water.This was one of the main reasons why last February, scientists forecast a nearly 80 percent chance that El Nio would soon fade to neutral, with a 55 percent chance that La Nia would take over during June through August.They got the first part right: El Nio did fade away. But its replacement by La Nia has been delayed. According to the latest forecast, issued by the National Oceanic and Atmospheric Administration in mid-December, there is a nearly 60 percent chance that La Nia conditions will definitively emerge by the end of January. But it is likely to be mild and short-lived. El Nio and La Nia are two sides of a climatic coin known as the El Nio Southern Oscillation, or ENSO. And La Nia is no less capable than its brother of influencing weather far and wide which is a good reason why we should care about it. In fact, even though it is likely to be relatively weak, the predicted La Nia could contribute to a notable dearth of precipitation this winter across the southern United States and Mexico, with enhanced precipitation in the Pacific Northwest and the Ohio and Upper Mississippi Valley regions.The Obstreperous SunOn May 14, 2024, the Sun unleashed a powerful, X8.7 solar flare at the time, the largest of the current solar cycle and the most powerful since 2003. It's visible in the lower right corner. (Credit: Screenshot of video from NASA's Goddard Space Flight Center)In 2024, the Sun's behavior reached a pinnacle of unruliness, officially entering the peak of its roughly 11-year activity cycle. Known as "solar maximum," this period is characterized by barrages of solar flares sudden, large eruptions of electromagnetic radiation; massive explosions of plasma and magnetic fields known as coronal mass ejections, or CMEs, which typically accompany flares; and increases in the solar wind.The image above shows the second most powerful solar flare of 2024 a massive burst of x-rays on May 14 that scientists measured as an X8.7 flare. X-class flares like this are the most powerful, being 10 times stronger than M-class, and 100 times stronger than C-class flares. During the year just ending, the Sun unleashed more than 50 of them. Flares and their associated CMEs can cause geomagnetic storms here on Earth. In addition to producing beautiful displays of the aurora borealis, geomagnetic storms can knock out satellites and power grids, and cause other serious disruptions. Because of the Sun's orientation toward Earth at the time, the coronal mass ejection accompanying the May 14 flare was not terribly disruptive. But a much smaller event a few days earlier was much more impactful. That's because the flare and CME were aimed directly at us. Among other impacts, it treated many millions of people to displays of the aurora borealis occurring much farther south than usual. (I'll have more to say about this year's wondrous auroral displays in Part 2 of this series.)Note: As I'm preparing this column on Dec. 30, the Sun has unleashed a series of flares, including a strong X-class flare, along with associated coronal mass ejections all directed at us. The result: A strong geomagnetic storm is expected that could trigger auroral displays overhead on New Years Eve as far south as Portland Oregon and New York City, and possibly visible on the horizon as far south as Oklahoma City and Raleigh, N.C., according to a forecast from the University of Alaska Fairbanks Geophysical Institute.Speaking of storms..."Extreme weather reached dangerous new heights in 2024," according to a report issued by World Weather Attribution in collaboration with Climate Central. "This years record-breaking temperatures fueled unrelenting heatwaves, drought, wildfire, storms and floods that killed thousands of people and forced millions from their homes."Millions of Texans experienced some of that mayhem starting on May 16, when a band of extreme thunderstorms spawned winds topping out at 100 miles per hour in the Houston area. The winds were especially long-lasting, qualifying the event as a "derecho."It was the most devastating wind event to impact the city in nearly 25 years, according to research to be presented at the upcoming 2025 American Meteorological Society conference. The derecho unleashed "destructive winds across a vast area, leading to widespread power outages and causing several fatalities," the co-authors write in their abstract. "Typically, Houston and the Gulf Coast are less susceptible to derechos, making this event particularly rare and alarming."An especially strong and long-lasting band of thunderstorms in Texas on May 16 and 17 produced long-lasting winds that reached 100 mph. Resulting widespread power outages in Houston continued for many days. This animation of images from the Suomi NPP satellite shows what that looked like from space. The before image is a composite based on data collected in April. The after image shows the scene on May 18. (Credit: NASA Earth Observatory)The power outages darkened large swaths of Houston, as seen in this stunning before-and-after animation of images from the Suomi NPP satellite. Nearly a million people were affected, some for days on end, leaving them without air conditioning as heat-index conditions soared to dangerous levels.To what extent was cimate change implicated in this extreme weather event? The research presented at the American Meteorological Society meeting in mid-January should answer that question in detail. But we do know this already: The severe storms exploded along the northern margin of a heat dome that was centered over Central America and the Caribbean. This large area of high pressure had stalled for many days, producing record-high temperatures over a large area, from Florida to Mexico. The waters of the Gulf of Mexico also were much warmer than the long-term average. And winds blowing across them swept sultry air into the Houston area high-octane fuel for thunderstorms. Ultimately, multiple factors came together in just the right way or I should actually say the wrong way to produce the severe weather. But in the background was climate change, which overall is making heat waves and extreme precipitation events worse. More Meteorological MayhemAn EF-4 tornado carved a path of destruction through Greenfield, Iowa, on May 21, 2024. With peak winds of 185 miles per hour, the twister's rampage through the little town is visible in this image captured by the Sentinel 2 satellite on May 25. (Credit: Modified Copernicus Sentinel data processed by Tom Yulsman)The year just ending saw an upsurge in another form of extreme weather in the United States: tornadoes. Through November, the year's preliminary tornado count was 1,762 among the highest on record for the January-November period. "Only 2011, 2008 and 2004 have a similar high count of tornadoes," according to NOAA.The satellite image above shows the severe impact one of this year's tornadoes on the town of Greenfield, Iowa. The twister spun up on Tuesday, May 21 in the southwestern part of the state. It then carved a path of destruction 44 miles to the northeast, ripping through tiny Greenfield, population 2,062, with 185 mile-per-hour winds. And those cataclysmic winds spread across a terrifying maximum width of more than a half mile.The result: A path of destruction through Greenfield that could easily be seen from space. Please stay tuned for Part 2 of this series, which will include compelling images captured from Earth orbit of wildfires, devastating Hurricane Helene, the Northern Lights, and more volcanic activity.
