Key Facts Of The Day 3/15

Storms and Flooding

• California’s 11th atmospheric river storm of the season dropped more rain and snow, sending thousands scrambling for higher ground and leaving more than 300,000 without power.
  • Los Angeles International Airport, downtown L.A., and the Santa Monica and Long Beach airports recorded new daily rainfall totals.
  • More than a dozen locations along major rivers overflowed as the high-impact storm moved south through the state, including areas along the Salinas, Sacramento, and Merced rivers.
  • At least 90 flood watches, warnings, and advisories were in effect statewide.
  • Portions of Mono and Inyo counties and the Lake Tahoe area were under avalanche warnings.
  • In the San Francisco Bay Area, the storm caused minor urban flooding, road closures, downed trees, and gusty winds of up to 50 MPH.
  • In Baldwin Hills, several mudslides were reported early Wednesday, including one that trapped two cars.
  • Santa Barbara County officials issued a mandatory evacuation order for residents around the burn scars of the Thomas, Alisal, and Cave fires, advising residents to leave immediately.
• Northeastern states were hit by a nor’easter that dropped several feet of snow in some places, leaving roughly a quarter of a million customers without power by Tuesday evening.
  • Five towns, including Marlboro, Vermont; Colrain, Massachusets; Moriah, New York; Stony Creek, New York; and Palenville, New York, accumulated 3 feet of snow by Tuesday night.
  • New York is under a state of emergency, as Gov. Kathy Hochul ordered emergency teams into place ahead of the storm.
• The parade of storms that have struck California in recent months has dropped more than 30 trillion gallons of water on the state.

Wildfire

• As of March 10, 4  large active wildfires have burned 4,178 acres across the country.
• As of March 10, 5,431 wildfires have burned 73,072 acres across the country.
• In Florida, 2 fires have burned 3,362 acres as of March 10.
• In North Carolina, 1 fire has burned 316 acres as of March 10.
• Due to an unusually wet winter in California, more grass is expected to grow this spring, and if dry conditions return, it could become wildfire fuel.

Extreme Heat

• As the global temperature has increased in recent years due to climate change, allergy season in the U.S. is starting earlier, and the amount of pollen during such periods has increased.
  • The early allergy season has also led to worse allergy and asthma symptoms for some and new symptoms for others.
  • Across North America, the pollen season length increased by 20 days, and pollen concentration increased by 21% between 1990 and 2018.
• Climate change is making atmospheric rivers much wetter and more intense, increasing the risk of potential flooding in California and other states along the West Coast.
  • Air over the Pacific will hold more moisture as sea temperatures rise, leading to giant rain and snow volumes.
  • Warming temperatures on land will cause more precipitation to fall as rain in the future, leading to more dangerous floods.

New Reports and Data

• A March 2023 study found that a recently developed scale for atmospheric river intensity can be used to rank atmospheric rivers and identify hotspots of the most intense atmospheric rivers worldwide.
• A March 2023 study found that only 0.001% of the global population is exposed to safe levels of daily ambient fine particulate matter.
• A March 2023 study found that high winds can worsen pathogen spread at outdoor chicken farms.