COLUMBIA — After months of drought capped by startling snowfalls, Pat Guinan's services were in high demand.
From last summer through March, the state climatologist traveled across Missouri interpreting more than a century of climate observations. It took a few weeks to get him in his office at Waters Hall.
Despite the uncertainty in applying national climate predictions to small areas, one local government has gone ahead with a formal climate adaptation plan.
The city and county of Boulder, Colo., jointly released a climate adaptation plan last summer.
"It's so challenging to dial down to the regional level," Lisa Friend, Boulder County's sustainability planner, said.
Boulder County has a varied environment, ranging from plains north of Denver to 14,000-foot mountain peaks on its western side. This added to the difficulty of climate planning, Friend said.
Boulder is prepared for extreme snow, but Friend listed some of the other issues weather poses:
- Heavy rains could test bridges and culverts and create flash floods.
- Drought could lower snow pack and stress drinking water sources.
- Increasingly dry years could result in more forest fires and less vegetation to halt erosion.
Boulder County had 23 separate plans that dealt with different pieces of climate adaptation, Friend said. The county government wanted to weave them all together, so it hired a local consultant to create a comprehensive climate preparedness plan.
"We're fortunate to have a consultant who really knew their science," Friend said.
The plan outlines specific policy recommendations and budget guidelines for four different sectors: water supply, emergency management, public health and agriculture and natural resources.
The county wanted to create what Friend called a no-regrets situation. That is, allocating resources to prepare for the worst, without wasting taxpayer money.
Friend said at first some Boulder County residents were worried that the plan was tied up with a United Nations conspiracy.
"We were able to convince them we have safety and welfare of Boulder County residents at heart," Friend said.
Jonathan Koehn, sustainability manager for Boulder, said the city uses the county plan to prepare for climate risks.
"We can't totally predict what's going to happen in the future," Koehn said. Yet making decisions based on incomplete information is better than doing nothing, he said.
"It would not be appropriate to not consider resiliency planning based on a clinical assumption that you can't talk about climate change," Koehn said. "The science would be a great backstop to say, like it or not, this is where things are more likely to head."
Unusually large snowstorms this winter closed MU twice, and one heavy, wet snow left thousands of Boone County residents without power. Guinan referred to a recent paper published in the Bulletin of the American Meteorological Society to explain the national trends in extreme snow events.
For the U.S. as a whole, “there were more than twice the number of extreme regional snowstorms from 1961 to 2010 as there were in the previous 60 years,” according to the paper compiled by climate modelers, meteorologists and statisticians from NOAA and several universities. They used more than 100 years of data from a network of thousands of government weather stations across the country.
Averaged across the U.S., heavy rain and snow events are increasing at 2 percent a decade, the authors state. These record storms are likely to continue, even during warmer- and drier-than-average seasons.
This trend challenges municipal governments as they consider plans for snow-clearing, stormwater management, maintaining water supplies and other weather-related expenses. A leading NOAA climatologist believes cities run a risk of under-designing for more extreme weather but recognizes that even the most comprehensive climate forecasts aren't specific enough for local governments to act with certainty.
Columbia had the greatest number of heavy snow events in the 1970s; the least snowy period on record was 1993-94 through 2009-10.
Guinan said a variety of local factors — latitude, elevation, topography and proximity to water, to name a few — can explain why a local trend doesn't match a regional, nationwide or global trend.
To illustrate what happens when averaging data across wide areas, Guinan pulled up a webpage with weather station data from across Missouri for April 16.
"We have temperatures that are running 15 to 20 degrees above normal across southern Missouri, 15 to 20 degrees below normal across northern Missouri," he said. "So when you combine those all together it would actually look like a normal day, but it's far from normal."
Global and national climate projections over the next several decades suggest "normal" is changing. But scaling that down to a single city or county is more difficult.
For now, the best place to look for such information is the most recent edition of the draft National Climate Assessment, released in January. It "describes the impacts across the country by region,” said Don Knapp, spokesman for a membership association of sustainability-minded local governments founded in 1990 as the International Council for Local Environmental Initiatives. The association has since changed its name to ICLEI Local Governments for Sustainability USA.
“It’s really powerful information local governments can use to help understand their risks and vulnerabilities and take actions based on the best science available,” Knapp said.
The assessment's section on the Midwest region that includes Missouri offers a few take-home messages:
- Extreme snow and rain events are more likely than in the past, especially in the Great Lakes region.
- Extreme heat, drought and floods pose threats to agriculture and public health.
- The ecological makeup of Midwestern forests, lakes and streams could change as plant growth zones move north and surface waters warm.
Ken Kunkel, a climate scientist with the NOAA Cooperative Institute for Climate and Satellites in Asheville, N.C., was also the lead author in the American Meteorological Society paper on trends in extreme storms. He acknowledged the assessment doesn't provide hard numbers on weather events for urban planners.
“I think people should be aware that if they design based on past weather, they may be under-designing,” Kunkel said. “The problem is they need a hard number for what the future would be.”
Kunkel explained that long-term climate models are similar to day-to-day weather forecast models, with some tweaks to allow them to run over a 100-year period. Modelers program computers to solve complex equations that describe the physics of fluids and energy. The models calculate hypothetical values of wind, temperature and precipitation, among other data.
“What we’re looking at is essentially a surrogate for what could actually happen in the future,” Kunkel said.
The models also factor in the addition of greenhouse gases to the atmosphere that trap more of the sun's energy and lead to higher temperatures and more extreme storms systems, he said.
Climate scientists use different and complementary models to understand climate. Some scientists use models that describe possible weather over the entire planet. These models become the foundation for other approaches. Other scientists look at specific regions by using regional models that take the information from global models and add more detail at the regional scale.
Kunkel said as many as 30 different computer models went into the National Climate Assessment. With each model delivering a somewhat different result, it’s impossible to answer, for example, exactly how many major snow events a region could see in a year.
“If model A says there’s going to be two, and model B says there’s going to be three, what information should people use?” he said. “That’s where we want to go with the assessment in the future, to provide more specific information.”
Until then, local governments have to grapple with uncertainty.
Columbia Public Works spokesman Steven Sapp said the city plans for a maximum of three to four snow events exceeding 4 inches per year. If the city starts getting more heavy snow dumps than that, they might have to add resources, he said.
Three of the past 20 years — 1993, 2011 and 2013 — had three to four days with more than 4 inches of snow. None of these years had more than four events.
“While there may be more heavy snowfall events in the future, will our area be hit every year? More than once a year? Wish someone could tell us for sure,” Sapp said.
Barbara Buffaloe, Columbia’s sustainability manager, said the city is discussing extreme weather more than when she took the job in 2010.
Columbia has been working to reduce its greenhouse gas emissions for years. In 2004, the city passed a renewable energy ordinance, and about 8 percent of the electricity Columbia Water and Light generated in 2012 came from renewable sources. In 2006, the city also became part of the U.S. Mayors Climate Protection Agreement to take local steps to reduce global warming.
“Hundreds of cities have set goals for reducing greenhouse gas emissions or have a climate action plan,” Knapp said. “Far fewer have taken actions on climate change resilience. It’s an emerging field."
Columbia does not have a plan on paper for adapting to a changing climate. Instead of a formal plan, climate change preparedness is "more of a series of discussions that we have,” Buffaloe said.
She said one such discussion dealt with snow plowing and city design: Streets laid out in grids are much easier to plow than cul-de-sacs, and Columbia has more than 1,100 of them.
"It's insane," Buffaloe said.
Sapp said each cul-de-sac presents a problem of where to put all the snow because the driver can't just dump it in front of somebody's driveway, mailbox or fire hydrant. The heavy, tandem-axle plow trucks the city uses on larger streets also can't turn well in a tight cul-de-sac, Sapp said.
For residential streets, Public Works used pickup trucks with plows mounted on the front to make tight turns and high loaders to scoop up snow and haul it away from a cul-de-sac, Sapp said.
But the lighter pickup trucks had a harder time cutting down to the pavement, and the high loaders moved slowly from cul-de-sac to cul-de-sac.
"It's all a balance," Sapp said. "We want to have adequate personnel, equipment and other resources to efficiently remove snow from Columbia's streets, but at the same time we can't purchase dozens of plows, high loaders or graders which may not be used more than one or two times a year."
No one can answer how many times a year Columbia will have to break out the plows over the coming decades.
When looking at historical weather patterns, Guinan expressed concern that Missouri communities might not be prepared even for weather extremes the state has seen before. He pointed to droughts over multiple years in Missouri’s past and offered a warning that if it happened before, it can happen again.
“We experienced numerous impacts with last year’s drought, and yet it was a young drought," Guinan said. "If anything, precipitation trends over the past 40 years have been unprecedented with respect to wetness in Missouri.”
“The 1930s was a decade dominated by drought, and the mother of all droughts was a five-year period in the 1950s,” he said. “We’ve had all these agricultural and hydrological impacts even though the state only began drying out last spring. So you can only imagine what would happen if the 1930s or 1950s were to repeat. There, of course, would be many more serious impacts.”
Supervising editor is John Schneller.