According to Climate Central, a non-profit news organization, spring temperatures across the contigous US have increased an average of 2°F over the past fifty years. The western part of the country has seen the largest seasonal upswing. Since 1970, Reno, NV has warmed 7.2°F and El Paso, TX has seen a rise of more than 5°F.
These warmer temperatures may feel like a boon for some, but they also bring a number of negative impacts. Less frost-free days means the allergy season is extended and disease-carrying pests like mosquitos and ticks are able to thrive longer.
Wildlife is also feeling the effects of a warming spring. The phenology, or timing, of important seasonal events like hibernation, migration, and pollination are being skewed from their once well-synced patterns.
Looking ahead, asgreenhouse gas emissionscontinue to increase, so too will the temperature and its accompanying impacts.
Across the contiguous United States, winter temperatures have increased an average of nearly 3°F over the past fifty years, according to Climate Central. The northern part of the country has seen the largest seasonal increase led by Burlington, VT with 6.8°F of warming since 1970.
Warmer winters may feel like a positive thing for some people, but they do not come without consequences. Periods of consistently cold temperatures help limit pest populations such as mosquitos and other pesky bugs. They also play an important role in plant development, especially for fruit trees that need a period of dormancy. Moreover, warmer winters threaten the livelihood of communities that depend on winter tourism, particularly ski resorts.
Looking ahead, asgreenhouse gas emissionscontinue to increase, so too will the temperature and its associated impacts throughout the year.
January, the so-called Dead of Winter, was unusually mild across much of the United States. No state in the Lower 48 ranked average or below average for the month, according to NOAA.
Taken as a whole, the mean temperature for the contiguous states was 35.5°F. At 5.4°F above the 20th-century average, January 2020 now ranks as the country’s fifth warmest January on record.
Regionally, the Northeast and Great Lakes were of particular note. Temperatures were much above average in both areas, with the Northeast posting its tenth warmest January and a large portion of the Great Lakes remaining unfrozen.
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.
Across the contiguous United States, autumn temperatures have increased an average of 2.5°F over the past fifty years, according to Climate Central. The western part of the country has seen the fastest seasonal increase, with Reno, NV warming 7.7°F. Las Vegas, NV, and El Paso, TX have each seen a rise of more than 5°F since 1970.
These warmer temperatures may feel like a summer bonus for some, but they also bring a number of negative impacts. Less frost-free days means the allergy season is extended and disease-carrying pests like mosquitos and ticks are able to live and thrive longer. Warmer temperatures also drive up energy bills, as people with air conditioning units use them longer into the season. This in turn, if they are powered by fossil fuels, adds even more heat-trapping greenhouse gases to the atmosphere.
Wildlife is also feeling the effects of a warming fall. The timing of when fruits ripen, for example, is being skewed from its “normal schedule”. In turn, this is impacting the once well-synced patterns of animal behaviors such as bird migration and hibernation.
Summer is the time of year when warm temperatures are expected. As our climate changes, however, the season is getting even hotter, especially at night.
Since 2010, according to NOAA, there have been 34% more record-warm low temperatures set than record-warm high temperatures. Nationally, summertime lows have increased an average of 1.8°F since 1895, according to an analysis by Climate Central, a nonprofit science news organization. The southwestern part of the country has seen the greatest warming, with Reno and Las Vegas, Nevada showing an increase of 16.9°F and 9.1°F respectively. Not far behind are El Paso, Texas at 7.7°F and Salt Lake City, Utah at 6.6°F.
In addition to climate change, land use issues also play a role in our warming nights. Paved surfaces hold more heat than vegetated ones, so cities tend to be hotter than rural areas, particularly during the overnight hours. This is known as the urban heat island effect.
When temperatures do not significantly cool off at night, people do not get a chance to recover from the heat of the day. This can cause serious health concerns, especially for young children, the sick, and the elderly. Warmer nights also drive up energy bills, as people with air conditioning units use them more. This in turn, if they are powered by fossil fuels, adds even more greenhouse gases to the atmosphere.
As the main author of the Declaration of Independence and the third President of the United States, Thomas Jefferson is regarded as one of this country’s Founding Fathers. He was also an astute and systematic weather observer.
Portrait of Thomas Jefferson by Rembrandt Peale, 1805. Credit: NYHS
In the summer of 1776, Jefferson was in Philadelphia, PA attending the Second Continental Congress, which adopted the Declaration of Independence. While there, he purchased a thermometer and a barometer – new and expensive weather equipment at that time. On July 4, Jefferson noted that the weather conditions in Philadelphia were cloudy with a high temperature of 76°F.
In an effort to understand the bigger picture of climate in America, Jefferson established a small network of fellow observers around Virginia as well as contacts in a few other states. According to records at Monticello, his estate in Virginia, he hoped to establish a national network for weather observations. While this plan did not come to fruition during his lifetime, today’s National Weather Service considers him the “father of weather observers.”
Happy Independence Day!
An excerpt from Thomas Jefferson’s Weather Journal, July 1776. Credit: NCDC
Across the contiguous United States, summer temperatures have increased an average of more than 2°F over the past fifty years, according to Climate Central, a non-profit science news organization. The western and southwestern parts of the country have seen the fastest seasonal increase, with places like Boise, ID, Las Vegas, NV, and McAllen, TX each warming more than 5°F since 1970.