Something unusual happened in the Pacific Ocean over the weekend: There were three hurricanes, all with category-four status at the same time, lined up across the central and eastern region of the world's biggest ocean.
Phil Klotzbach, a research scientist at the tropical meteorology project at Colorado State University, said that this was the first time in modern recorded history they've seen three storms of that level coexisting in that region of the Pacific. But, he and other experts added that good satellite data only goes back three to four decades, so it's possible that it has happened before.
"The fact that you can get three category-fours in one basin is impressive," Klotzbach told VICE News, referring to the section of the Pacific to the east of the international date line. "And I think it's especially impressive given that two of those category-four storms were in the Central Pacific." That region, which spans 140 degrees of longitude to 180 degrees, isn't usually conducive to hurricanes, he said.
The storms were Hurricanes Ignacio and Jimena, plus Kilo, which was down graded to typhoon after it crossed the dateline.While Ignacio is now a tropical storm, Hurricane Jimena had maximum sustained winds of 115 miles per hour as of Tuesday night, according to the Central Pacific Hurricane Center.
This animation of images captured August 29 to September 1 from NOAA's GOES-West satellite shows Hurricane Ignacio near Hawaii, followed by Hurricane Jimena and Tropical Depression 14E. (Video via NASA/NOAA GOES Project)
Tropical cyclones in the Northern Hemisphere are called hurricanes when in the Atlantic Ocean and central and eastern parts of the Pacific Ocean. They're known as typhoons in the western Pacific.
The culprit behind the increased activity is El Niño, Klotzbach and other experts said, which brings warmer waters to the central and eastern Pacific, making it more favorable to hurricane formation. The waters off Hawaii are especially warm, Klotzbach said.
This hurricane season is breaking records, he added, with 15 tropical cyclones of category four or five appearing so far in 2015, all of them in the Pacific. The previous record, Klotzbach said, was nine.
"In the age of modern hurricane tracking, which is the last 30 to 40 years … , this is the first time we have seen three category fours alive and well and threatening in the Central and Eastern Pacific," William Patzert, a climatologist at NASA's Jet Propulsion Laboratory, told VICE News.
Like Klotzbach, Patzert pointed at the warm waters brought about by El Niño, which occurs every 2 to 7 years, when sea surface temperatures in the Eastern Pacific become anomalously warm, saying storms like this could be expected.
"I've never seen such a large area, so warm, so early, and at the peak of the heating season which is the reason you're seeing all this right now," Patzert added.
Patzert cautioned against attributing the hurricanes to global warming and said that while climate change is a real threat to the globe for a variety of reasons, the data isn't yet clear on whether or not it will cause stronger or more frequent hurricanes.
Kevin Trenberth, a senior scientist at the National Center for Atmospheric Research in Boulder, Colorado, said that global warming was indeed part of the equation. He said that he had expected this lively hurricane action in the Pacific because of El Niño, and that this year reminded him of 2005 in the Atlantic — the year Hurricane Katrina struck New Orleans.
The oceans are absorbing heat from climate change, having warmed by over a degree Fahrenheit since the 1970s, he said, and that heat is fuel for hurricanes, which leave cooler waters in their wake.
"The best way to think about it, is that when global warming and natural variability [like El Nino] are going in the same direction — and that's what's happening in the Pacific — that's when you have very active seasons, and that's when you're apt to break records, and see some things that you've never seen before, like three category-four hurricanes in the same basin," Trenberth told VICE News.
The season has indeed been "very active," Alejandro Ludert, a research assistant at the Pacific ENSO Applications Center, a research center in Hawaii, told VICE News. He said they were already seeing their ninth storm of the season, which is well above normal. Like other experts, he chalked the increase up to El Niño.
But another phenomenon is at work besides El Niño, said Gabriel Vecchi, a climate scientist and oceanographer at NOAA's Geophysical Fluid Dynamics Laboratory in Princeton, New Jersey.
"I would say there is an El Niño going on right now, however our analysis is that this El Niño is not the most important cause for the big increase of activity in the central Pacific," Vecchi told VICE News.
Instead, he said, there is very warm "blob" of water, a huge swath of the Pacific that is warmer than usual, above the equator, extending from Mexico out through Hawaii. He thinks it is that stretch of warm water — not caused by El Nino — that is driving the hurricane activity. But he is unsure of the reasons behind the warm patch.
As for global warming, Vecchi said that the general scientific consensus now is that by the year 2100, hurricanes might be slightly more powerful, but that the total number of them globally would either stay the same or decline slightly.
Meanwhile, something rare also happened in the Atlantic, where a hurricane traveled through Cape Verde, just off the coast of Africa. That hurricane, called Fred, was probably the "eastern-most hurricane on record," Richard Pasch, of the National Hurricane Center in Miami, told VICE News.
Fred was "very unusual," Dave Nolan, of the Department of Atmospheric Sciences at the University of Miami, told VICE News. A warm patch of water between the islands and Africa, he said, helped in its formation.
What caused the water to warm there, he said, remains unknown.
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