2019 also marked the 43rd consecutive year with a global temperature above its long-term norm. That means every year since 1977 has posted a warmer than average annual temperature.
Looking at the map below, it is clear to see that heat dominated most of the planet last year. The only continent that did not post an annual temperature among its top three highest was North America. It ranked fourteenth. The state of Alaska, however, experienced its warmest year on record.
The exceptional warmth of 2019 is largely attributed to the long-term trend of human-caused climate change. While a weak El Niño was present at the beginning of the year, it dissipated by July with ENSO neutral conditions prevailing afterward.
Looking at the bigger picture, the five warmest years on record have occurred since 2015, and nine of the ten warmest have taken place since 2005. The only year from the last century included on the top ten list is 1998, which ranks tenth.
As greenhouse gases – the main driver of global warming – continue to spew into the atmosphere, temperatures will continue to rise and records will likely continue to fall.
Global temperature records date back to 1880.
2019 was Earth’s second warmest year on record. Credit: NOAA
While above-normal precipitation was observed across much of the nation, some places were particularly wet. North Dakota, South Dakota, Minnesota, Wisconsin, and Michigan each posted their wettest year on record. Another 18 states finished in the top ten.
Months-long flooding in the upper Midwest and Mississippi River basin caused a tremendous amount of damage to farms and homes across the region. In fact, the combined cost of the Missouri, Arkansas, and Mississippi River floods was $20 billion. That adds up to about half the total cost of the 14 different billion-dollar weather and climate disasters that occurred in the US during 2019.
Heavy rain events and flooding are nothing new, but experts say climate change is making them worse. As greenhouse gases warm the atmosphere, the air is able to hold more water vapor. With evaporation from oceans, rivers, and lakes increasing, there is more water vapor available to condense and fall as rain.
Weather records for the contiguous United States date back to 1895.
The calendar says January, but it felt more like early May in New York City this weekend.
In Central Park, the temperature soared to 69°F on Saturday and hit 68°F on Sunday, setting new record highs for both dates. According to the NWS, the previous records of 63°F for January 11 and 66°F for January 12 were set in 1975 and 2017, respectively.
It is also interesting to note that the overnight low temperatures for both dates (51°F and 43°F) were warmer than the normal high. The average high for the city in mid-January is 38°F and the average low is 27.
The primary driver of this unseasonable warmth was a large ridge in the jet stream. Sitting over the eastern part of the US, it allowed warm air from the south to flow further north than it normally would at this time of the year.
But, as with most things that go up, they must also come back down. The temperature is expected to moderate over the next few days but remain above average. More seasonable temperatures are expected to return by the end of the week. So, don’t put your winter coats away just yet.
The “Dead of Winter” is an old saying that refers to the coldest part of the winter season. For most of the northern hemisphere, that usually means the month of January.
While actual daily weather varies, historical average temperatures typically reach their lowest point of the year between January 10 and February 10. In the US, the western half of the country, with the exception of high elevation areas, tends to see its coldest day before the eastern half. This is because the mountainous areas of the west and much of the eastern US tend to be snow covered in winter, reflecting much of the sun’s heat. Here in New York City, mid to late January is usually the coldest part of the winter season.
Air temperature depends on both the amount of energy received from the sun and the amount of heat lost or absorbed by the oceans and continents. From the start of winter through mid-February, both the oceans and land are losing more heat than they gain.
Art and science have come together at the New York Hall of Science to highlight the fascinating world of weather. In a group exhibition titledWeather the Weather, artworks of various mediums explore the different ways we understand and experience the forces of nature.
Curated by Marnie Benney, this SciArt Initiative exhibition features the work of twenty-one artists from around the world. Honored to be one of them, images from my American Glaciers: Going, Going, Goneand Wildfires series are on display.
The exhibition will be on view through February 20, 2020 at The New York Hall of Science, 47-01 111th Street, Queens, NY. For hours and directions visit www.nysci.org
The Earth reached its Perihelion today at 7:48 UTC, which is 2:48 AM Eastern Standard Time. This is the point in the planet’s orbit where it comes closest to the Sun.
This annual event is due to the elliptical shape of the Earth’s orbit and the off-centered position of the Sun inside that path. The exact date of the Perihelion differs from year to year, but it’s usually in early January – winter in the northern hemisphere. The Earth will be furthest from the Sun in July.
While the planet’s distance from the Sun is not responsible for the seasons, it does influence their length. As a function of gravity, the closer the planet is to the Sun, the faster it moves. Today, the Earth is 147.1 million kilometers (91.4 million miles) away from the Sun. That is approximately 5 million kilometers (3 million miles) closer than it will be in early July. This position allows the planet to speed up by about one-kilometer per second. As a result, winter in the northern hemisphere is about five days shorter than summer.
The word, perihelion, is Greek for “near sun”.
Earth’s Perihelion and Aphelion. Credit: Time and Date.com
New York City experienced some noteworthy weather in 2019, especially the dramatic swings between hot and cold temperatures almost every month. In the end, however, these extremes just about balanced each other out. The city’s average temperature for the year in Central Park was 55.6°F, which is 0.7°F above normal.
In the end, only four months produced below-average readings. Of those, November posted the greatest departure from average with a temperature of 3.85°F below normal. This was aided by the two record cold overnight lows that occurred that month.
On the other side of the spectrum, two months posted temperatures among their top ten warmest on record. April 2019 was the third warmest April and July 2019 was the tenth warmest July ever recorded in New York City.
The summer brought NYC a number of oppressively hot and humid days, including 15 days withtemperatures in the 90s. The hottest day came during the mid-July heatwave when the mercury soared to 95°F. When humidity was factored in, the heat index or real feel temperature was in the triple digits.
On the precipitation side of things, 53.03 inches of rain was measured in Central Park. That is 3.09 inches above average. Of that soggy total, 7.09 inches came down in December, making it the fifth wettest December on record in NYC.
Snowfall, on the other hand, was somewhat scarce. Only 16.6 inches was reported in Central Park. However, it is interesting to note that the vast majority of that total, 10.4 inches, fell during the first few days of March. The city, on average, gets 25.8 inches for the calendar year.
Records for the Central Park Climate Station date back to 1873.
December 2019 felt like a weather roller coaster in New York City. Highs ranged from a relatively balmy 58°F to a frigid 25°F. But in the end, these extremes nearly balanced each other out. The city’s mean temperature for the month was 38.3°F, which is only 0.8°F above average.
Credit: The Weather Gamut
In terms of precipitation, December was a month for the record books. The city received 7.09 inches of rain in Central Park, making it the fifth wettest December on record. It is also interesting to note that two different days produced rainfall totals greater than one inch. Snowfall, however, was below average. Only 2.5 inches was reported in Central Park. New York City, on average, sees 4 inches of rain and 4.8 inches of snow in December.