NYT: Decades of extraction have left the South American rainforest at a “tipping point.”

The Amazon has long served as a vast carbon sink, even as vegetation pumped oxygen into the atmosphere to the point it was called the “lungs of the Earth.”

But vast deforestation, despite calls to save the Amazon that originated decades ago, portends profound changes in the ecology of the huge, increasingly fragmented forest that lies mainly within Brazil.

“Just in the past half-century, 17 percent of the Amazon — an area larger than Texas — has been converted to croplands or cattle pasture. Less forest means less recycled rain, less vapor to cool the air, less of a canopy to shield against sunlight,” according to a report from Alex Cuadros.

“In one study, a team led by the researcher Paulo Brando intentionally set a series of fires in swaths of forest abutted by an inactive soy plantation. After a second burn, coincidentally during a drought year, one plot lost nearly a third of its canopy cover, and African grasses — imported species commonly used in cattle pasture — moved in.”

The sun breaks through the clouds in a South Knox County neighborhood on Tuesday morning following days-long subfreezing temperatures and snowfall Monday night. Thomas Fraser/Hellbender Press

Southern cities emerge from frigid airmass after Christmas weekend of brutal cold and snow

KNOXVILLE — Temperatures rose above freezing on Tuesday for the first time since Dec. 23 following a weekend bout with historic cold, high winds, burst water and sewage lines and power outages. The chaos was punctuated with unexpectedly potent snowfall Dec. 26 on frigid roadways that snarled traffic in the city and metro area.

The snow came in the wake of a brutal cold front that first moved into the region in the early hours Friday morning. 

Snow didn’t start falling until Monday afternoon, and by sunrise Tuesday between .5 and 2 inches of the white stuff had blanketed the area, falling upon already frigid roadways.

Public safety officials across the region urged motorists to stay home, and numerous government offices either closed or got off to a late start Tuesday due to icy roads.

Both the Knoxville Police Department and Knox County Sheriff’s Office activated their Severe Weather plans, which meant that officers would only respond to emergencies and wrecks with injuries.

Crews from the city used brine and rock salt to treat streets designated as Level I (main thoroughfares like Kingston Pike and Broadway) and Level II (connector roads like Sutherland Avenue and Martin Luther King Jr. Boulevard).

In Great Smoky Mountains National Park, where more than 4 inches of snow fell, officials closed several roads, including the Gatlinburg Bypass, Foothills Parkway West, Laurel Creek Road at the Townsend Wye, and Little River Road from the Sugarlands Visitors Center to the Townsend Wye.

Among the lower elevations in the East Tennessee Valley, Blount County had the most snow with 2 inches on the ground; most of Knox County registered 1.5 inches, according to meteorologist Allan Diegan of the National Weather Service office in Morristown.

While the snow brought its own share of problems and excitement, many people were still recovering from a bitter cold front that swept through the region over the Christmas weekend.

While some native East Tennesseans can remember even colder storms, the type of single-digit temperatures seen from Dec. 23 to 25 came as a surprise to many residents, according to Diegan.

“I wouldn’t say this was rare by any means, but it normally doesn’t happen in December,” Diegan said. “Our coldest days are usually in January and February. This just hasn’t happened in several years, so for people who are just now moving here it might be a little different than what they expected.”

At Knoxville’s McGhee-Tyson airport, the mercury fell as low as 4 degrees early Friday morning, which was the lowest reading on a Dec. 23 since 1988, he said.

But that was by no means the coldest temperature ever recorded in the Knox County area, stressed Diegan — that record was set on January 21, 1985, when the mercury dropped to a bone-chilling 24 degrees below zero.

“I don’t think we saw any daily low records broken this weekend, which is kind of hard to believe,” he said. “This was, at least, the coldest it’s gotten since 2015.”

On February 20, 2015, the low in Knoxville was 3 degrees, records show.

One record that was set in Knoxville over the weekend was for the lowest recorded high temperature for December 23, said Diegan. The high on Friday never climbed above 22, which broke the record of 24 set in 1989.

The blast of cold Arctic air that wreaked havoc over much of the nation last week was so intense it managed to bring single-digit lows even though there wasn’t any snow on the ground until the cold front had already blown through.

“Typically, it takes us having snow on the ground that’s followed by a clear night for the temperatures to drop so low,” he explained. “Cloud cover acts like a blanket and solar radiation is trapped. When it clears, the solar radiation escapes and the temperatures tend to plummet.”

So what was the coldest spot in East Tennessee over the past few days and who got the most snowfall?

Unsurprisingly, Diegan said the answer to both questions was Mt. LeConte in the Great Smoky Mountains National Park.

Weather equipment installed on the 6,593-foot-tall mountain went as low as 22 degrees below zero on Christmas Eve and, after Monday’s snow storm, approximately 4.5 inches of precipitation was on the ground. 

Previous updates and the original article are below:

UPDATED Dec. 23: Rolling blackouts, icy spots and subzero wind chills are only some of the challenges facing hundreds of thousands of people across East Tennessee and the Southern Appalachians as a Siberian cold front barrels through the region.

In Knox County, up to 26,000 KUB customers had lost power at one time due to a combination of wind damage and a massive surge in demand for electricity. High temperatures in the Knoxville area hovered near 10 degrees throughout Dec. 23.

If your power went out for up to an hour today, in a home or commercial establishment  it was likely due to rolling blackouts imposed on local utilities by the Tennessee Valley Authority.

“TVA is requiring KUB to reduce power load due to extreme demand on the electric system,” Knoxville Utility Board said in a press release.

“KUB customers are likely to experience temporary outages until TVA provides more information,” according to a statement released in the early afternoon of Dec. 23 by officials at the utility. “KUB is striving to keep rolling outages to 15 minutes and is rotating outages across the service area until TVA lifts the requirement.”

The planned outages were stopped around 1:30 p.m. but around 7,200 customers remained without power due to the high winds at that time, KUB’s website said. 

The cold front — which has wreacked havoc and shattered records across much of the continental United States — roared into the Tennessee Valley in the early morning hours Friday, driving temperatures down into the single digits as winds gusted up to 40 mph.

The lowest recorded temperature in Knox County was 3 degrees in Karns; the low in downtown Knoxville stood at 7 degrees, said meteorologist Allan Diegan. 

The real danger came from the wind chill, which was estimated at 5-10 degrees below zero in the early morning hours, he said. The good news was the roads were mostly clear, with few areas in the Tennessee Valley seeing more than a dusting of snow.

The mercury isn’t expected to climb above freezing until Monday, although the winds should begin to diminish on Saturday.

The rolling blackouts triggered confusion and no small amount of swearing in Fountain City during the noontime “lunch rush.” Power went out along Broadway just before 12 p.m., forcing surprised store clerks and restaurant managers to ask their customers to leave until the situation could sort itself out. 

“I can’t believe I drove down here for this,” said 44-year-old Debra Wells of Halls as she walked back to her car in the Kroger parking lot. “I was going to get lunch at the deli but now it looks like I can’t even go to Chik-Fil-A (across the street).”

One manager at Kroger shook his head apologetically when asked when the store would reopen. “No idea,” he said as he locked the front doors. 

The grocery store reopened within the hour, however — just as power was cut to thousands of customers in the residential areas of the Fountain City and Inskip neighborhoods for about 20 minutes.

One of the biggest concerns this weekend has been the safety of the hundreds of men, women and children who live on Knoxville’s streets, according to officials from Knox Area Rescue Ministries (KARM).

A white flag has been flying outside KARM’s emergency shelter for the homeless on North Broadway, signaling that normal rules restricting who can stay there have been temporarily waived.

“People have been streaming in all day long,” said KARM spokesperson Karen Bowdle. “There are probably close to 450 people in the building. There so many people that they’ve separated the men into the chapel and the women into the dining room.”

Karen said that KARM crews had even been taking meals and coffee to the City’s warming station across the street. 

“We’re very grateful, and we’re all trying to work as a team,” she said. “There are a lot of people who will die across our country this weekend.”

The original Hellbender Press article continues below:

A historically brutal cold front expected to move into East Tennessee late Thursday has people across Knox County and beyond bracing for a potentially deadly drop in temperatures.

The approaching storm is expected to shatter low-temperature records as the temperature drops as low as 7 degrees Dec. 24, the coldest temperature ever reported in Knoxville on Christmas Eve, according to officials from the National Weather Service station in Morristown.

“The biggest concern is the wind chill,” said NWS meteorologist Kyle Snowdin, who said that daytime highs on Friday are expected to hover in the mid-teens. “There will be wind gusts of 30 to 40 mph, which means we could see temperatures of negative single digits or even negative double digits.”