Humans have just experienced what will go down as the hottest year in recorded history -- so far -- as the planet experienced heating at an unprecedented pace.
Throughout 2023, records for the warmest temperatures around the world were broken one by one. But record-eclipsing temperatures will no longer be an anomaly if greenhouse gas emissions that fuel global warming continue at the current pace, according to climate scientists.
In short, hotter-than-normal temperatures could soon become the norm if fossil fuel extraction does not significantly decrease before 2030, the next big deadline for many countries to meet their climate goals.
Emissions need to be reduced by 45% by 2030 and reach net zero by 2050 to keep global warming to no more than 1.5 degrees Celsius since Industrial Revolution temperatures -- the threshold outlined in the 2015 Paris Agreement -- according to the United Nations.
"Climate change is here," U.N. Secretary-General Antonio Guterres told reporters during a press conference in July, amid scorching temperatures all over the planet. "It is terrifying. And it is just the beginning."
Here are some of the most consequential stories of extreme heat from 2023:
Summer 2023 brought unparalleled stretches of triple-digit temperatures throughout the southern U.S.
El Paso, Texas, saw a record stretch of 44 consecutive days at or over 100 degrees in June and July, smashing the previous record of 23 consecutive days set in 1994, records show.
Phoenix, Arizona, saw a record-shattering stretch of 31 days at 110 degrees or greater, surpassing the previous record of 18 consecutive days.
Death Valley National Park saw 17 consecutive days over 120 degrees, from July 14 to July 30, according to the National Park Service.
Worldwide, the planet reached its hottest day ever recorded for four days in a row in July.
"It really was the summer in particular in which the climate crisis came home to people across America," Miranda Massie, founder and director of the Climate Museum in New York City, told ABC News.
Before this past summer, 2022 was the ocean's warmest year on record. But in the summer of 2023, it managed to surpass that record.
Ocean temperatures off the coast of Florida soared to 101 degrees at the hottest points in the summer.
Marine temperatures began heating up early in the season. By July, temperatures were 4 degrees to 7 degrees above average for that time of year, which proved fatal for much of the coral reef in the area.
A mass coral bleaching event occurred in Florida during that time, followed by the rest of the Caribbean shortly after.
Oceans absorb about 90% of the heat generated by emissions. And since water is much more difficult to heat than land, it also takes much longer to cool.
The warm waters also serve as a super fuel for hurricanes that form in the Atlantic basin.
Climate change is making Atlantic hurricanes twice as likely to strengthen from weak to major intensity in 24 hours, a study published in October in Scientific Reports found.
Scientists have been keeping a close eye on melting in the poles due to the regions' ability to cause drastic sea level rise.
In February, Antarctica's sea ice extent, which serves as a buffer for some of the largest melting glaciers, reached a record low for the year.
By August, Antarctica saw its fourth consecutive month with the lowest sea ice extent on record, according to the National Oceanic and Atmospheric Administration.
In October, the ozone hole over Antarctica grew to one of the largest on record, and a study published that same month found that it may be too late to prevent significant melting on the West Antarctic ice shelf that includes Thwaites, known as the "Doomsday Glacier" because its melting could cause global sea levels to rise by about 10 feet, according to climate scientists.
This year marked the hottest summer on record for the Arctic.
The Arctic is warming two to three times faster than the global average, which already dramatically affecting Arctic ecosystems, according to the National Oceanic and Atmospheric Administration's 2023 Arctic Report Card.
There were large big declines in Arctic snow cover in late spring, and the sixth-lowest sea ice extent on record, well below the long-term average, Rick Thorman, a climate scientist with the University of Alaska, Fairbanks' International Arctic Research Center, said earlier this month with the release of the report.
Changes in water temperatures have led to growths in algae and plankton and have caused drops in the abundance of Chinook and Chum Salmon, along with a dramatic increase in the Sockeye Salmon population, which is affecting local economies near Bristol Bay, Alaska, as Chinook are the largest and most profitable salmon to harvest, according to the report.
"The time for action is now," NOAA Administrator Richard Spinrad said during a presser at the American Geophysical Union Conference in San Francisco on Dec. 12.
Several months in 2023 broke records for being the warmest-ever on Earth, researchers said.
June was the warmest on record. July was the hottest month ever recorded. August was the warmest on record. September was the warmest on record. October was the warmest-ever recorded.
The emergence of autumn did not bring relief to high temperatures.
On Nov. 7, Amarillo, Texas, hit an all-time November high at 88 degrees, while temperatures in Hollis, Oklahoma, soared to 95 degrees -- the hottest temperature in the state so late in the season, according to the National Weather Service.
The abnormally warm conditions then spread to the eastern seaboard, bringing temperatures in the 80s as far north as Virginia.
For the first time on record, the global average temperature surpassed 2 degrees Celsius above pre-industrial levels on Nov. 17, according to a preliminary analysis from Copernicus, Europe's climate change service.
This past November was also the warmest on record, while September to November 2023 was the warmest autumn on record for the Northern Hemisphere, according to a report by Copernicus.
The record heat then spread to the eastern seaboard, bringing temperatures in the 80s to Delaware and Washington and stretching south to Northern Florida.
December saw record warmth as well, including the mildest Christmas Eve ever for the Upper Midwest in the U.S.
The 2024 Minnesota Ice Festival was even canceled ahead of the Christmas holiday due to unseasonably warm weather, which raised safety concerns for both ice construction workers and visitors.
As of mid-December, less than 16% of the nation was covered in snow, the lowest amount since 2006, with snow deficits continuing to grow.
Marquette, Michigan, is more than 3 feet below average to date for snowfall, while Duluth, Minnesota, is almost 2 feet below average, and Minneapolis about 10 inches below average.
New York's Central Park keeps obliterating its old record, nearing 700 days without 1 inch or more of snow.
Several reports and studies show that climate change is accelerating and the impacts are getting worse, especially when it comes to extreme heat.
NOAA, Copernicus, the the U.N. and the World Meteorological Organization all released reports recently that said 2023 has been the warmest year on record.
As a result, the impacts of climate change are getting much worse, according to the WMO.
The most effective and efficient solution will be the immediate halting of fossil fuel extraction, which will have an immediate effect on the amount of greenhouse gases being admitted into the atmosphere, experts say.
Greenhouse gas emissions from fossil fuels are projected to reach a record 36.8 billion metric tons in 2023, an increase of 1.1% over 2022, according to an annual report by the Global Carbon Project.
"What we're seeing is an intensification of business as usual on the fossil fuel front," Massie said.
"What we need to do is raise our voices about all that and make it clear that business as usual is no longer acceptable," Massie added.
ABC News' Stephanie Ebbs, Melissa Griffin, Max Golembo and Kelly Livingston contributed to this report.