3 Hurricanes in the Pacific Show the Power of El Niño

Three hurricanes are spinning across the Pacific Ocean at the same time, and scientists say a strong weather pattern called El Niño is largely to blame. The storms — named Karina, Lowell, and Marie — formed this week and reached powerful levels. Climate scientists say this kind of activity is exactly what they expect during an El Niño year, especially one as strong as this one.

Hurricane Lowell is the most dangerous of the three storms right now. It reached Category 5 strength on Wednesday, the highest level a hurricane can reach, before weakening to Category 3. The storm is moving west but is expected to turn sharply north this weekend, possibly passing near the Hawaiian islands of Oahu and Kauai.

Hawaii has already had a rough stretch of weather this year. The state was hit by flash flooding and strong winds from Tropical Storm Lala just weeks ago. Before that, severe floods in March dropped more than 25 inches of rain on parts of Oahu and more than 19 inches on parts of Maui, leaving behind damage that hasn't fully been repaired.

Hurricane Karina has weakened from a Category 3 to a Category 2 storm east of Hawaii, and forecasters expect it to keep losing strength. Hurricane Marie is near Mexico's Baja California Peninsula and is actually getting stronger. Large ocean swells from Marie could affect Mexico's coast and possibly Southern California this weekend.

El Niño is a natural weather pattern that causes parts of the Pacific Ocean to become warmer than usual. When ocean water is warmer, it gives storms more energy to grow bigger and stronger. This year's El Niño is expected to be one of the strongest ever recorded, with water temperatures at least 2 degrees Celsius above normal.

Scientists compare tropical storms to car engines that run on warm ocean water as fuel. Daniel Gilford, a meteorologist at the research group Climate Central, says that more warm water means storms can grow more powerful. "If we increase the amount of fuel available to a storm, it's kind of like increasing the speed limit on your car," Gilford said.

The Pacific Ocean was already very warm before El Niño even began this year. Scientists tracked a large marine heat wave — a long stretch of unusually high ocean temperatures — that started in the Pacific last year. Climate Central found that about 94% of the Pacific has experienced heat wave conditions since January.

While the Pacific is very active, the Atlantic Ocean has been unusually quiet — and that is also a sign of El Niño. El Niño changes wind patterns in a way that stops storms from forming in the Atlantic. Scientists say both effects are classic signs of El Niño at work.

Many scientists believe that climate change is making El Niño stronger over time. A study in the journal Science found that El Niño events have grown more powerful since humans began burning fossil fuels, which release gases that trap heat in the atmosphere. United Nations Secretary-General António Guterres called the situation urgent, saying El Niño is "being supersized before our eyes."