Now there’s emerging research to suggest that cosmic rays, or positively charged, high-energy particles from space, might be the mechanism that flips the switch between phases. Cosmic rays come from outside our solar system, but the number and intensity that reach Earth hinge on the magnetic field of the sun.
The cracked and desiccated shoreline of Lake Mendocino made a telling backdrop for California Governor Gavin Newsom’s message at a news conference last week: Drought conditions are here, and climate change makes the situation graver. But water supplies vary across regions, which is why the governor limited a drought emergency declaration to just two northern counties. In fact, highly urbanized Southern California has a record 3.2 million acre-feet of water in reserve, enough to quench the population’s needs this year and into the next.
Earth’s rising fever hit or neared record hot temperature levels in 2020, global weather groups reported Thursday.
While NASA and a couple of other measurement groups said 2020 passed or essentially tied 2016 as the hottest year on record, more agencies, including the National Oceanic Atmospheric Administration, said last year came in a close second or third. The differences in rankings mostly turned on how scientists accounted for data gaps in the Arctic, which is warming faster than the rest of the globe.
Global warming pushed temperatures into record territory in 2020, in effect tying 2016 as the hottest year on record, according to data released Thursday by U.S. science agencies.
Last year’s average global surface temperature was 2.2 degrees Fahrenheit above the late 19th century average, according to NASA. It was the fifth consecutive year of more than 2 degrees above that base line. Indeed, the seven hottest years in 140 years of record keeping are the last seven. In descending record order, they are 2020 and 2016, 2019, 2017, 2015, 2018 and 2014.
Parts of the world economy may have been on pause during 2020, dampening greenhouse gas emissions for a while. But that didn’t slow the overall buildup of atmospheric carbon dioxide, which reached its highest level in millions of years.
If anything, research during the year showed global warming is accelerating. Symptoms of the fever include off-the-charts heat waves on land and in the oceans, and a hyperactive and destructive Atlantic hurricane season.
There isn’t a one-size-fits-all approach to forecasting climate patterns when there’s an El Niño or a La Niña pattern in place.
El Niño and La Niña patterns are part of the El Niño Southern Oscillation, which monitors sea-surface temperatures in the equatorial Pacific Ocean.
When sea-surface temperatures in this region are above average, it’s called El Niño; when they are below average, it’s called La Niña.
We aren’t talking about major changes in water temperatures but typically more minor swings — usually on the order of plus or minus a degree Celsius — 1.8 degrees Fahrenheit — or less.
There are instances when water temperatures have been as much as eight degrees Fahrenheit above average — a very strong El Niño — but it’s not common.
Federal scientists say that La Niña — the phenomenon where Pacific Ocean waters off South America are cooler than normal — is underway this winter.
A commonly held assumption among many Californians is that La Niña means a dry winter is coming, and in years when the opposite occurs, El Niño, a wet winter is considered more likely.
So brown lawns and water rationing are just around the corner, right?
Not necessarily. Looking at historical records, there isn’t a clear pattern. In the Bay Area, La Niña years have been drier than normal only about half the time.
La Niña is back.
It’s been a couple of years since satellites and buoys detected the mass of cold water forming along the equator. National Weather Service meteorologist Alex Tardy said when you average out the effect of La Niñas over the last few decades, they tend to indicate we’re in for less precipitation than what we’d get in an average winter.
Climate forecasters said Thursday that the world had entered La Niña, the opposite phase of the climate pattern that also brings El Niño and affects weather across the globe. Among other impacts, La Niña has the potential this winter to worsen what are already severe drought conditions in the American Southwest.
La Niña conditions were observed in the Pacific Ocean last month, and there is a 75% chance the weather pattern will persist through the winter, forecasters with the National Oceanic and Atmospheric Administration said.
