Extreme Weather and Climate Change:

Extreme Weather and Climate Change: The Northeast

WHAT WE KNOW

On average, the US is 2 degrees F warmer than it was 40 years ago. Twice as many record highs have been set in the past decade as record lows, in the US. By 2050, record highs could outpace record lows by 20 to 1 in the U.S. By the end of the century, the ratio could jump to 100 to 1 if greenhouse gas emissions continue unabated. This warmer world is increasing the odds of extreme precipitation, in part because a warmer atmosphere can hold more moisture and release more of it during rainstorms and snowstorms. Heavy precipitation, both rain and snow, is happening more often than it used to. Heat-related extreme events are on the rise around the globe. Man made climate change significantly increased the odds of some specific events, including the killer European heat wave of 2003 and the Russian heat wave of 2010. Even small increases in average temperatures raise the risk of heat waves, droughts and wildfires.

Devastating deluges, record floods and deadly heat waves have raised the question of whether there’s a connection between these events and global warming.

The bottom line answer is yes: Heat waves are longer and hotter than they used to be and some regions are suffering from catastrophic drought.  Heavy rains are more frequent and can be more intense and rainfall records have been smashed. These events fit a pattern that climate scientists have long expected to appear as the result of increased greenhouse gases in our atmosphere. That doesn’t mean global warming is the only culprit: extreme weather was happening before global warming began. But there’s general scientific agreement that global warming has contributed to a trend toward more intense extremes of heat and precipitation around the world, is partly to blame for specific extreme weather events over the last decade and will continue to influence both in the future.

THE NORTHEAST

Major Rainstorms and Floods of 2011

A quick summary of 2011 weather highlights would read approximately like this:  Devastating snowstorm, devastating snowstorm, blizzard, heat wave, heat wave, torrential rains, hurricane (more torrential rains), floods, hurricane remnants (even more torrential rains), worse floods, even more devastating snowstorm—and that only takes you through October. The details follow.

RECORD SMASHING RAIN
2011

All-Time Rainiest Month:
August 2011
Central Park, NY (18.95”)
La Guardia, NY (17.32”)
JFK, NY (17.24”)
Newark, NJ (18.79”)
Philadelphia, PA (19.31”)

Rainiest August of All Time
Binghamton, NY, (8.90”)
Trenton, NJ, (16.10”)
Allentown, PA (13.47”)

Rainiest September of All Time
Dayton, OH (10.84”)
Baltimore, MD, (13.32”)
Binghamton, NY,  (16.58”)

Rainiest August-September of
All-Time
Philadelphia, PA (29.58”)
Wilmington, NJ (20.63”)
Baltimore (26.46”)

Rainiest Year Ever *
(and it’s not over yet!)Cleveland, OH (53.84”)
Scranton, PA (54.02”)
Binghamton, NY (52.70”)
Harrisburg, PA (61.82”)
*January through September 2011

• In late August, Hurricane Irene became the first hurricane to make landfall in New Jersey in more than 100 years, dumping 6 to 8 inches of rain in parts of New Jersey, New York, Massachusetts, Connecticut and Vermont. This was on top of the 6 to 8 inches that had already fallen in August.
   
• In early September, Irene was followed by more heavy rain due in part to the remnants of Tropical Storm Lee which caused several Mid-Atlantic and Northeastern states to experience historic flooding (Pennsylvania, New York and Virginia) and in Pennsylvania alone forced 75,000 people to evacuate and destroyed 2,000 homes.
   
• The September rains swelled the Susquehanna and Delaware Rivers to record-breaking levels in Binghamton and Owego, NY, and Waverly and Wilkes-Barre, PA, to name just a few.
   
• In Hershey PA, Swatara Creek crested at 26.8 feet, beating the previous record by more than 10 feet.
   
• Flood damage, which is estimated at around $1 billion, was especially severe because the rains fell on a region that had already been saturated with drenching rainfall in the preceding weeks and months including from Hurricane Irene in late August.
   
• On September 8th, a whopping 7.03 inches of rain fell in Ft. Belvoir, VA., in just three hours. According to the National Weather Service (NWS), that amount of rain in that amount of time was “off the charts above a 1000-year rainfall (based on precipitation frequency from Quantico).” Largely due to Tropical Storm Lee, Pennsylvania recorded its rainiest September on record, according to the National Climatic Data Center. January through September was the rainiest such period on record in New Jersey, New York, Pennsylvania and Vermont.

Major Snowstorms of 2011

The blizzard that paralyzed New York City shortly after Christmas 2010 was followed by record-breaking snowstorms in the Northeast and Midwest during January and February.

Six cities saw their snowiest January on record: Hartford, CT (57.0 inches), Bridgeport, CT (42.0 inches); Newark, NJ (37.4 inches); Central Park, NY (36.0 inches); Islip, NY (34.3 inches); and LaGuardia Airport, NY (32.6 inches). Hartford’s 57 inches of snow in January made it the city’s all-time snowiest month on record.

 Thanks to reduced sea ice in the Arctic Ocean in summer and fall, the Arctic has been unusually warm. Recent research suggests this may have changed air circulation patterns in winter, pushing colder than normal air down toward North America and Europe (22, 23, 24). 

An unusually early major winter storm that struck the Mid-Atlantic and Northeast in late October, 2011 caused widespread tree damage and power outages and contributed to 22 deaths. The storm, nicknamed “Snowtober”, knocked out power to more than three million customers from West Virginia to Maine and resulted in the largest power outage in Connecticut’s history. Dropping up to 32 inches of snow, it was the most severe early-season snowstorm in New England since befo

\re the Civil War. According to one insurance company estimate, Snowtober resulted in upwards of $3 billion in damage.

2011 Heat Records

April 2011 was the warmest April on record for Portland, ME, New York, NY and Atlantic City, NJ.

June 2011 was the warmest June on record for Philadelphia, PA.

Philadelphia, PA, Trenton, NJ and Atlantic City NJ, all set records for the most days ever above 90°F.

Summer 2011 was the hottest summer on record for Boston, MA and Windsor, CT.

Extreme Weather and Climate Change: The Midwest

Spring 2011 brought some of the worst flooding in history, from the Upper Midwest to the Gulf of Mexico. Snowmelt and more than three times the normal spring rainfall in the Ohio Valley made rivers, including the Ohio, Missouri and the Mississippi overflow their banks along with many smaller tributaries. The Mississippi River crested at either record or near-record levels from Illinois all the way to Louisiana.

More than 1,300 daily precipitation records were broken during April across the Midwest and South. For the month, 72 locations reported their rainiest day in any April on record and five of these stations set a new all-time record for the rainiest 24-hour period for any month, the National Climatic Data Center reported.

On May 2, the Army Corps of Engineers breached part of the Birds Point-New Madrid Levee near where the Ohio and Mississippi Rivers come together, flooding 130,000 acres of Missouri farmland, but protecting the small Illinois town of Cairo.

 

On May 9, officials opened the Bonnet Carre Spillway in Louisiana, which diverted floodwaters into Lake Pontchartrain. Later, officials also opened part of the Morganza Spillway to reduce pressure on levees that protect New Orleans from flooding. In Minot, North Dakota, the overflowing Souris River forced about 11,000 residents to evacuate and flooded 4,000 homes. Waters from the Mississippi River flooded Yazoo City, Mississippi, where the crest reached 38.7 feet, close to the record set during a devastating flood in 1927, and nearly ten feet above flood stage. In Memphis, the Mississippi crested at 47.9 feet, the highest there since 1937. The 2011 flood also set an all-time record in Vicksburg, Mississippi where the Mississippi crested at 57.1 feet on May 18. In Natchez, Mississippi, the river rose about four feet higher than the previous record set in 1937.

The Missouri River also caused record floods due to above average spring precipitation and a record to near-record snowpack that contributed large amounts of river runoff. In Wyoming and Montana for the month of May, a total of 14 locations set precipitation records and seven locations set a new all-time record for the rainiest 24-hour period for any month on record.  According to the National Climate Data Center, the flooding resulted in at least $800 million of damage to Mississippi agriculture, $500 million in damage to Arkansas agriculture and $320 million in overall damages to Memphis, Tennessee. Overall, roughly 3.5 million acres of farmland were flooded in the Lower Mississippi Valley including 900,000 acres in Mississippi (that’s 10 percent of the state’s total) and 1 million in Arkansas. Across the nation, 6.8 million acres of farm and non-farm land were inundated during the spring of 2011 — one of the worst flood disasters in American history.

2011 Snow Storms

While most of the headline-grabbing snowstorms of 2011 affected Northeastern cities like New York, the Midwest was slammed as well, especially by a blizzard that struck in early February, paralyzing a region that is used to plenty of snow. According to NOAA, the "Groundhog Day Blizzard," which crippled travel in the Midwest and stranded motorists on Lakes Shore Drive in Chicago, dropped one to two feet in some areas, with 22 states getting at least five inches of snow. The Groundhog Day Blizzard was one of Chicago’s top five snowstorms on record. It caused more than  $1.8 billion in total losses and 36 weather-related deaths.

 2011 Heat

In mid July, much of the nation sweltered under a “heat dome” that brought roasting heat and sweltering humidity to much of the eastern two thirds of the country. At its worst, more than 140 million Americans were under a heat advisory or excessive heat warning, with the heat index—a measure of discomfort that combines both heat and humidity and describes how hot it actually feels—reaching brutal levels typical of the area surrounding the Red Sea in Saudi Arabia.

THE SOUTHWEST

Number of days the maximum temperature exceeded 100 °F. credit: NOAA/NCDC.

Extreme Heat and Drought of 2011

 Texans love to brag about how big their state is along with everything in it. Not so much this year, though, as record-breaking heat, drought and wildfires relentlessly pummeled Texans. The heat struck nearby Oklahoma, Louisiana and New Mexico too, pushing all of the states’ resources, along with their residents, to the brink of disaster—and in many cases, right over the edge. Scientists know that climate change is making heat extremes like those experienced in the Southwest this year more intense and more frequent.

What happened in 2011:

Texas, Oklahoma, New Mexico and Louisiana had their hottest summers on record this year. 

Texas had the warmest summer of any state in the U.S. going back to when modern records began in 1895 and set more than 4,000 hot temperature records in August alone. Oklahoma came in second and both states beat records set during the Dust Bowl era in the 1930s. Nationally, the ratio of record highs to record lows this summer was 4.35 to 1. But in Texas, the ratio was 80 to 1.

 

In Texas, the average statewide temperature for the summer (night and day) was a whopping 86. 8°F.

 Every state in the Lower-48 except North Dakota and Vermont had at least one day with a temperature topping 100°F. Many cities broke all-time heat records.  Austin, Texas set new records for the most 100° days, the hottest month, the hottest summer and the hottest day in history (112°F, tied with Sep, 5, 2000)

Climate change is creating drier conditions in the American Southwest,(15) and has been linked to increases inforest acres burned in some regions of the West.(8,16)

 

These drier conditions are aggravated by natural climate cycles, such as La Nina, a significant factor in this year’s drought, which tend to favor drought in the Southwest. Global warming could boost the intensity and impact of these La Nina-related droughts.(18,19,20)

 

For every additional degree of global warming, the number of acres burned in Southwest wildfires is projected to increase dramatically — at the same time as rain and snowfall decrease.(17)

At the end of September, 97 percent of Texas was in one of the top two most severe categories of drought, according to the U.S. Drought Monitor. That’s a new state record.

 

Drought and extreme heat combined to create Texas’ worst wildfire season on record, with nearly four million acres burned so far. Texas broke a record for the driest 12-month period on record. The drought has cost Texas an estimated $5.2 billion in agricultural losses and at least $1 billion in other damage, making it the most costly drought in the state’s history.

The drought is driving up the price of beef as ranchers are forced to sell their herds early. Lower cotton yields could force up cotton prices and peanut, corn and wheat crops have also been hit hard. The Bastrop fire, which ignited east of Austin on September 4, burned over 34,000 acres, killed two people and destroyed more than 1,600 homes, breaking the state record for the most homes lost in a single wildfire. It was also the most expensive wildfire in Texas history.

 

New Mexico also suffered from unusually severe wildfires. At one point, the Las Conchas wildfire, which burned nearly 130,000 acres, threatened the Energy Department’s Los Alamos National Laboratory, the birthplace of the atomic bomb.