Research via the Rocky Mountain Climate Organization

Devastating extreme rain events are part of a growing trend in the Midwest, according to a new report looking at 50 years of storm data.

Over the last five decades, the types of deluges that washed out towns in Iowa, forced the Army Corps of Engineers to intentionally blow up levees to save Cairo, Illinois, and sent the Missouri River over its banks for hundreds of miles, have been increasing, according to analysis by the Rocky Mountain Climate Organization (RMCO) and the Natural Resources Defense Council (NRDC).

Big storms, leading to big floods, are occurring with increasing frequency in the Midwest, with incidences of the most severe downpours doubling over the last half century. The report’s lead author, Stephen Saunders, explained that “a threshold may have been crossed”:

“Global studies already show that human-caused climate change is driving more extreme precipitation, and now we’ve documented how great the increase has been in the Midwest and linked the extreme storms to flooding in the region.

In addition to region-wide trends, the report presents trends in the eight Midwestern states.  For the worst storms (three inches or more of rain in 24 hours) from 1961-2011, the report outlines the following state-level trends:  Indiana (+160 percent); Wisconsin (+203 percent); Missouri (+81 percent); Michigan (+180 percent); Minnesota (+104 percent); Illinois (+83 percent); Ohio (+40 percent); and Iowa (+32 percent).

Key findings include:

• Since 1961, the Midwest has had an increasing number of large storms.  The largest of storms, those of three inches or more of precipitation in a single day, increased the most, with their annual frequency having increased by 103 percent over the roughly half century period through 2011. For storms of at least two inches but less than three inches in a day, the trend was a 81 percent increase; for storms of one to two inches, a 34 percent increase. Smaller storms did not have a significant increase.

• The rates of increase for all large storms accelerated over time, with the last analyzed decade, 2001-2010, showing the greatest jumps. For the largest storms, in 2001-2010 there were 52 percent more storms per year than in the baseline period.

• The frequency of extreme storms has increased so much in recent years that the first 12 years of this century included seven of the nine top years (since 1961) for the most extreme storms in the Midwest.

• With more frequent extreme storms, the average return period between two such storms has become shorter. In 1961-1970, extreme storms averaged once every 3.8 years at an individual location in the Midwest. That is two to four times more frequent than a major hurricane making landfall at a typical location along the U.S. coast from North Carolina to Texas. By 2001-2010, the average return period for Midwestern extreme storms at a single location was down to 2.2 years—or four to eight times more frequent than landfalling major hurricanes.

The report also presents new evidence linking extreme storms in the Midwest to major floods, the region’s most costly regularly occurring natural disasters.

The new analysis shows that the two worst years in the Midwest for storms of three inches or more per day were 2008 and 1993, the years with the Midwest’s worst floods in some 80 years, which caused $16 billion and $33 billion in damages and rank,  among the nation’s worst natural disasters. The report presents new evidence linking the 2008 flooding to extreme storms, showing that in areas with the worst flooding 48 percent of the local precipitation came from extreme storms.

In 2010, which ranked fourth among years in regional extreme-storm frequency, Iowa alone had $1 billion in agricultural losses from extreme storms. In 2011, which ranked fifth, Midwestern flooding caused $2 billion in damages. This shows how the Midwest is increasingly vulnerable to flooding if extreme precipitation continues to increase with human-caused climate change, as scientists consistently project will happen.

This research brief was originally published at the Rocky Mountain Climate Institute.

Even with the wettest April on record, some areas of England are still facing “exceptional” drought conditions. After two years of dry winters — including the fifth-driest March — the ground hasn’t been able to soak up the heavy rainfall that hit in April.

The situation in the country illustrates the cruel reality of “rollercoaster” extreme weather — a problem that will only be exacerbated by accumulating heat-trapping gases in the atmosphere. Recent research also finds that the loss of Arctic ice favors extreme, prolonged weather events “such as drought, flooding, cold spells and heat waves.”

The rain has certainly helped some regions. But other parts of England were so dry, it could take months of record rainfall to bring groundwater levels back to normal. One aquifer close to London is 90 percent below normal levels for this time of year.

Experts in the country are explaining why the combination of extremely dry and extremely wet conditions make it harder to recover from drought. Climatewire reported on the problem:

“Heavy rain on parched ground is like pouring water on an old, dry sponge. Much of it will bounce off. The sponge needs to be wet in order to hold the water. Farmers are in a much better position than they were thanks to the rains. River levels have risen, soil moisture has increased and their water reserves have been replenished. But aquifers take much longer to fill,” said a spokeswoman for England’s Environment Agency.

According to figures from the Environment Agency, 42 percent of groundwater “indicator sites” are “exceptionally low.”

“Over the last two winters, the amount of rainfall we have had has been down 20 to 30 percent on what we would normally have. Most of the recharge of groundwater happens over the winter. We lost three to four months of groundwater recharge in total over that two-year period,” [explained Andrew McKenzie of the British Geological Survey McKenzie to Climatewire.]

“We have now had the wettest April ever, and you might think that would go halfway to recharging the groundwater. But we also had a very dry March, and the soils had already switched to summer, dry mode and had to switch back,” he added.

Ironically, when the rains hit in April after a dry March, the Environment Agency issued 13 severe flood warnings and 42 flood alerts for areas around the country — all while homeowners were banned from watering their gardens.

This will eventually be normal weather under a business as usual emissions scenario.

According to a study from the National Center for Atmospheric Research, our current rate of emissions puts us on a path to dust bowl conditions in many areas of the world, while “precipitation may become more intense but less frequent (i.e., longer dry spells) under GHG-induced global warming. This may increase flash floods and runoff, but diminish soil moisture and increase the risk of agricultural drought.”

Related Posts:

• Must-See Video: Has Global Warming Caused A Quantum Jump In Extreme Weather?
• NOAA: Human-Caused Climate Change Already a Major Factor in More Frequent Mediterranean Droughts
• Study: Global warming is driving increased frequency of extreme wet or dry summer weather in southeast, so droughts and deluges are likely to get worse

by Peter Lehner, via NRDC’s Switchboard

In a recent PBS documentary, the mayor of Norfolk, Virginia, Paul Fraim, talks about how flooding has become a monthly occurrence in his town, and how global warming and sea level rise are as much a daily issue for him as education and fighting crime. In some parts of Norfolk, streets turn into rivers at high tide. Homes are flooded five out of six years. People lose their carpets, their appliances, their savings. And they can’t afford to move elsewhere.

Sea levels have risen 14 inches in Norfolk since 1930–almost double the global rate. Part of this alarming change is due to the natural sinking of the area’s soggy tidal lands, but part of it is due to the rising sea levels brought about by global warming. Like stranded polar bears in the North Pole, like disappearing island nations in the Pacific, waterlogged Norfolk is yet another symbol of global warming at work. And even though Norfolk is within spitting distance of our nation’s capital, Congress still hasn’t seemed to grasp the seriousness of the situation.

Turning a blind eye to the realities of global warming is a dangerous game. Scientists predict that sea levels will rise anywhere from 7 inches to 78 inches in the next 100 years (depending, in part, on how much we do to curb global warming pollution), which means that in a few generations, nearly five million people who currently live within 4 feet of high tide could be in the same boat as the residents of Norfolk.

New research shows that global warming will double the chance of a hundred-year flood occurring in many locations within the next 18 years. In some areas, the chance is tripled.

Nearly half the states in the nation will be affected by rising sea levels. Despite these odds, for the most part, we are financially, structurally, and administratively unprepared to deal with the most immediate consequences of global warming.

Bailing out after a flood is a major expense not only for swamped cities, but for taxpayers all over the country. FEMA, the Federal Emergency Management Agency, spent more than $100,000 per home in Norfolk to raise residences above expected water levels. The National Flood Insurance Program (NFIP), run by FEMA, is nearly $18 billion in debt, and has had to borrow money from the Treasury to stay afloat.

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by Sarah Murdock

At a time when 80 percent of Americans believe Congress is doing a poor job, there is an opportunity for lawmakers to take action on an issue that would impact many millions of citizens: flood insurance reform.

And, here’s the amazing part — it’s got major bipartisan support. Like football.

The National Flood Insurance Program (NFIP) within the Federal Emergency Management Agency (FEMA) makes flood insurance available to coastal and inland property owners for homes and buildings that are mapped in areas of flood risk. It’s a critical service.

Unfortunately, the Program in its current form is fatally flawed. It actually encourages increased risks to people, property and nature.

This flaw is due in large part to subsidized flood insurance that pays people to rebuild again and again in areas where floods and hurricanes put communities, first responders and properties at risk.

To make matters worse, development in flood risk areas has the perverse effect of destroying natural systems that would otherwise provide flood and storm protection to people and properties.

Then there’s the fact that the current program does not emphasize “preventative-care” solutions that would greatly reduce the cost of flood damage during extreme events. One recent study estimated that for every dollar spent on flood preparedness, five dollars are saved when disaster strikes.

But, here’s perhaps the biggest problem: in a world of increasing severe and erratic storms and floods, as well as sea level rise, these issues are beginning to have more devastating consequences. In 2011 alone, there were 58 Federal flood disaster declarations, covering 33 different states, costing over $8 billion and causing 113 deaths. Both the costs and the number of deaths exceeded the 30–year averages.

What’s more, in a report commissioned by FEMA, findings indicate that there will be a 40 to 45 percent increase over the next century in U.S. areas susceptible to flooding.

Enter The Flood Insurance Reform and Modernization Act of 2011.

The bill passed the House last summer by a vote of 406-22 and the Senate banking committee unanimously last fall. It needs to pass the full Senate by May 31^st, before the flood insurance program is scheduled to sunset altogether.

Last week, I testified before the Senate banking committee on why The Nature Conservancy – and the diverse Smarter Safer coalition, of which we are a member – supports the legislation, with a focus on fixing the fatal flaw of the current Program.

The bill will eliminate subsidized rates, allow rates to be adjusted to reflect true risk, and take into account future impacts from increased storms and floods. Currently there are 1.2 million properties (20% of the Program) that are charged premiums well below the value of the insured liability.

This pricing fix works in tandem with the bill’s increased focus on flood mitigation – the “preventative care” strategies I mentioned earlier.

The traditional approach to flood protection has been to rely on dams and levees to contain floodwaters, and to build sea walls and bulkheads in coastal areas. While this “grey” infrastructure plays an important role in helping to secure our communities, it’s expensive to build and maintain. What’s more, an over-reliance on it in the U.S. in the past hundred years has encouraged extensive land development in areas particularly susceptible to floods and storms – and catastrophic damage when infrastructure fails. And, fail it has. Look no further than Hurricane Katrina.

Instead of relying solely on grey infrastructure, the bill will make it easier for flood insurance grant programs to fund oftentimes cheaper and more flexible “green infrastructure” solutions – such as restoring coastal wetlands, oyster reefs, and barrier beaches, as well as restoring river connectivity and restoring forests to ensure sufficient floodplain areas.

The reality is, we’ll need both green and grey solutions. But, right now, most planners don’t think beyond the grey stuff.

And, natural systems give us benefits we can’t get from a wall or levee, such as cleaner water, protection against erosion, more recreation opportunities, and food (bringing back fish and shellfish populations, and maintaining agricultural production).

It’s good policy, and it’s a hit on both sides of the aisle. Time for the Senate to take it to the finish line.

For folks interested in showing support for the legislation, check out our Use Your Outside Voice site.

Sarah Murdock is a senior policy advisor at The Nature Conservancy.

Report Looks at Five Major Health Threats From Flooding in a Warming World

A Union of Concerned Scientists news release

WASHINGTON (March 15, 2012)—Extreme precipitation and flooding, likely on the rise in a warming world, carry significant and often hidden health risks, according to a report, “After the Storm: The Hidden Health Risks of Flooding in a Warming World,” released today by the Union of Concerned Scientists (UCS).

“Damage from floods is typically measured in terms of lives lost and the cost of damage to buildings and infrastructure,” said Liz Perera, UCS public health analyst and one of the report’s co-authors.  “But what are often overlooked are the potentially costly public health impacts.”

The report calls attention to these impacts by listing the top five health risks of extreme precipitation and flooding:

1. Drowning while driving: Almost half of 2010 flood fatalities involved people who drowned while attempting to drive through floodwaters. Only 18 inches of water can lift a car or SUV; once buoyant, the water will easily push the vehicle sideway. Most vehicles then tend to roll over, trapping those inside.
2. Waterborne diseases contaminating drinking water: Extreme precipitation and flooding can sometimes overwhelm drinking water infrastructure and wells, which reduces or prevents water purification. Over half of all waterborne disease outbreaks in the United States occur in the aftermath of heavy rain.
3. Sewage back-up in plumbing or basements: Flooding can cause local sewage lines and septic tanks to overflow, sometimes resulting in sewage backing up into people’s residences.
4. Bacteria, sewage, and other contaminants in waterways: During flooding, untreated sewage, pesticides, and street contaminants (motor oil, dog excrement, etc.) can flow into local rivers, lakes, ponds, and even ocean beaches.
5. Mold and dangerous indoor air quality: Water intrusion anywhere in a building can cause toxic mold to grow in ceilings, walls, or insulation.

“Over half of all outbreaks of waterborne diseases in the U.S. occur in the aftermath of heavy rains,” said Perera.  “Health risks will likely increase as extreme rainfall events are projected to become more common in a warming world.”

Heavy rains can contaminate drinking and recreational water with sewage, petroleum products, pesticides, herbicides, and waste from farm animals, wildlife and pets. Floodwaters may contain more than 100 types of disease-causing bacteria, viruses and parasites.

“We think of waterborne illnesses as a problem in developing countries, but it’s a very real public health issue here in the U.S.,” said Dr. Marc Gorelick, division chief of pediatric emergency room medicine at Children’s Hospital of Wisconsin, in Milwaukee. “Climate change, because it likely causes heavier storms, could threaten our already vulnerable water supply and lead to more cases of gastrointestinal illness.”

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Our guest blogger is Alice Thomas, Climate Displacement Program Manager, Refugees International. In May, 2011, Alice wrote how the extreme floods of Colombia were devastating the nation. This post describes Colombia’s continued fight for survival in our poisoned climate.

As we approach the town of Manatí, in northern Colombia, I look eagerly out the window for signs of change. When I was here almost a year ago, makeshift shelters and tents lined the sides of the road. Random pieces of furniture were piled nearby: a refrigerator or a rocking chair – anything people could save from the floodwaters.

Today the tents are gone. But just outside of town, we turn off the road and into a lot, where temporary shelters made of fiberboard and corrugated metal have been constructed. I see Irida emerge from one of them. Smiling and laughing, we embrace each other.

Irida is one of approximately 225,000 people who were affected when unprecedented rains in the fall of 2010 caused the nearby Dique Canal to rupture. The break in the canal, which connects Colombia’s coastal city of Cartagena to the Magdalena River, submerged half of the northern state of Atlántico under 80 million cubic meters of water. When I first visited Manatí in March 2011, half of the town was still underwater, and Irida was living under plastic sheeting after being evicted from the local school. Irida’s house, which she showed me by canoe, had water up to the rooftop.

To some extent, Irida was lucky. Hers was one of the first families in the town able to move into these temporary shelters last April. In many of the nearby towns we have visited, they were not completed until three months ago.

But the shelter where Irida now lives was designed to last only three months. She has been there for almost a year. Worse than that, the floodwaters have still not dissipated, and her house is still flooded. According to the state governor’s office, 60 percent of the area that flooded when the Dique Canal burst in 2010 is still underwater today. Pumping has proven ineffective because much of this area was once wetland and is now returning to its natural state. So Irida and the roughly 600 other families in Manatí who’ve lost their homes are now being told they will have to relocate.

The day after our reunion with Irida, we join a town hall meeting where the governor tells a schoolyard full of flood-affected families that his priority is to find land and build homes for the thousands still displaced more than a year later. But Irida tells me that she doesn’t want to take the piece of land being offered. It is too far away from the center of town, she says. Before the floods, she ran a small grocery shop out of her house. If she relocates, she will be unable to restart her business and will be isolated from her community.

Like so many other Colombians we are meeting on this trip, Irida is quick to smile and laugh. But the pain and anxiety are nevertheless visible on her face. Beyond the relocation troubles, she has many more immediate worries. The toilets at her temporary shelter do not work, and two of the plastic water tanks have recently ruptured in the heat. The Colombian government discontinued food deliveries to the area in November. Her husband has been unable to find work. Without permanent homes or work, how can the process of recovery even begin?

I am at a loss for words as we say our goodbyes. I hope things will be better for Irida the next time we meet; I wish I could be more certain.

As carbon pollution accumulates in the atmosphere, our weather is growing more intense and unpredictable, threatening the health of the union. Following the freakishly warm and dry start of this January, extreme storms then pummeled the nation:

WASHINGTON ICE STORM: “A monster Pacific Northwest storm coated the Seattle area in a thick layer of ice Thursday and brought much of the state to a standstill, sending hundreds of cars spinning out of control, temporarily shutting down the airport and knocking down so many trees that members of the Washington State Patrol brought chain saws to work. East of Seattle, a man was killed by a falling tree as he was backing an all-terrain vehicle out of a backyard shed, authorities said.” 90,000 customers of Puget Sound Energy lost power.

OREGON FLOODS: With a persistent flow of Pacific moisture targeting the Pacific Northwest, several inches of rain have fallen across the western third of Oregon. Widespread flooding has developed with Salem, Corvallis and Philomath just some of the cities that have dealt with the worst of the rising waters. Torrential rain swept away a car from a grocery store parking lot, killing a mother and her one-year-old son.

NEVADA WILDFIRE: A destructive wildfire erupted shortly after noon on Thursday and raced quickly through the dry countryside surrounding Reno, NV, propelled by wind gusts of 82 mph. At its height, the fire forced evacuation calls for some 10,000 people. The fire destroyed 29 homes over six square miles before a storm on Saturday brought precipitation after the region’s driest winter in recorded history. Reno had no precipitation at all in December.

JANUARY TORNADOES: Last Tuesday, a powerful storm front spawned one EF-1 tornado in metropolitan Louisville, Kentucky, and a second hit near Madison, Indiana. At least 10 tornadoes struck the South overnight Sunday as a powerful storm system moved across the Great Lakes and into southern Canada, killing two in Alabama. The tornadoes were spawned along the southern end of a front that arced through the eastern US like a comma’s tail, bringing severe thunderstorms, hail, and twisters to Arkansas, Mississippi, Alabama, and Tennessee before moving into Georgia later Monday morning.

Extreme weather is wreaking increasing damage on the people of the United States. With cutbacks in local, state, and federal government services, continued inaction on fighting greenhouse pollution, and ideological opposition to preparing for the ravages of unchecked climate change, the state of our union is under threat.