An audible murmur ran through the crowd when images of flooding in Hamburg and the Glenwood, Iowa, area flashed on the screen.
They’d come to Creighton University on Sunday to hear noted climate scientist James Hansen speak about global warming, but in the back of so many minds was that climate change isn’t about polar bears and sea level rise. The consequences can be felt in the heart of a continent, too.
More extreme weather is one of the three most destructive effects of climate change, Hansen told the crowd. The two others are sea level rise and species extinction.
Taken by themselves, floods such as those that occurred in March in Nebraska and Iowa don’t prove much, he said, but a look at weather globally does. “There is an increased frequency of climate extremes, which is not natural,” he said with the slide as his backdrop. “People around here should recognize climate extremes.”
An Iowa native and former director of the NASA Goddard Institute for Space Studies, Hansen has been credited with bringing global warming to the national consciousness during testimony before Congress in 1988.
Global warming is amping up the worst kinds of weather, from greater heat and drought to more intense storms and heavier precipitation.
“The 100-year flood now occurs more than once a century, and don’t be surprised by a 500-year flood,” he said.
“Dry places (like the Middle East and U.S. Southwest) become drier, wet places (like Southeast Asia) become wetter,” he said. “At a place that is sometimes wet and dry (like Nebraska), those extremes tend to get greater.”
Photos: Major flooding hit Nebraska and Iowa towns in March 2019
People watch from the Huron Street bridge as water from Willow Creek flows just under bridge in Missouri Valley, Iowa on Wednesday, March 13, 2019.
The junction of Highway 275 and Highway 91 is flooded on Wednesday, March 13, 2019 just north of Scribner, Nebraska.
Cody Stump walks through a flooded street in Hooper, Nebraska, on Wednesday, March 13, 2019.
High water rolls through a street in Hooper, Nebraska, on Wednesday, March 13, 2019.
High water floods a street in Hooper, Nebraska, near a trailer park on March 13.
High water floods a street in Hooper, Nebraska, near an old bank building on Wednesday, March 13, 2019.
Standing water from melting snow and rain reflects the evening sky as a truck travels north on Highway 275 near Fremont, Nebraska, on Wednesday, March 13, 2019.
Crews from the Ashland, Mead and Yutan Fire and Rescue assist with evacuating the final residents in Ashland, Nebraska om Thursday, March 14, 2019.
Crews from Ashland, Mead and Yutan Fire and Rescue assist with evacuations in Ashland. Sixteen temporary shelters in Nebraska opened to take in such evacuees.
Nebraska State Patrol Trooper Keith Bell surveys the water levels as floodwaters continue to rise near Salt Creek in Ashland, Nebraska, Thursday, March 14, 2019.
Sean Hanger, of Ashland and his son Aiden, navigate the floodwaters which continue to rise near Jack Anderson Ball Park in Ashland, Nebraska, Thursday, March 14, 2019.
Floodwaters continue to rise as mailboxes are consumed near Furnas Street and N. 15th Street in Ashland, Nebraska, Thursday, March 14, 2019.
Residents are rescued from a flooded area near Missouri Valley, Iowa on Thursday March 14, 2019.
Jenna Muntz stands behind a row of sandbags as she takes a photo of the rising floodwaters in Cedar Creek, Nebraska on Thursday, March 14, 2019.
A semitrailer truck that tried crossing Bell Creek in Arlington, Nebraska, was swept off the road by fast moving floodwaters.
Both Iowa and Nebraska were hit hard by flooding earlier this year and are in need of the disaster aid. Bell Creek, on the east side of Arlington, Nebraska flooded parts of the town on Thursday, March 14.
Blake Japp pulls his remote control truck out of the water while playing in the shallow floodwaters of Bell Creek on Thursday, March 14, 2019, in Arlington, Nebraska.
Bell Creek, on the east side of Arlington, Nebraska flooded parts of the town on March 14.
People navigate over giant chunks of ice that were thrown by floodwaters near River Resort in Yutan, Neb Thursday March 14, 2019.
A flooded home near Mosquito Creek in Council Bluffs, Iowa on Thursday, March 14, 2019.
Two corn cobs float in floodwaters near Mosquito Creek in Council Bluffs, Iowa on Thursday, March 14, 2019.
A Blackhawk helicopter hovers over Waterloo on Friday March 15, 2019.
A cow makes his way through floodwaters near Columbus, Nebraska on Friday, March 15, 2019.
A house is surrounded by floodwaters near Waterloo, Nebraska on Friday, March 15, 2019.
Floodwaters run through the town of Rogers, Nebraska on Friday, March 15, 2019.
Highway 75's northbound lane is closed due to flooding near Merritt's Beach RV Park on Friday, March 15, 2019.
Cars drive drive across a flooded Platte River on Highway 50 just north of Louisville on Friday, March 15.
Water covers a road near Valley, Nebraska on Friday, March 15, 2019.
Brent Schwindt of Norfolk, Nebraska, holds his son Paul, 4 months, as his wife Lacey Hansen sleeps on a blow up mattress at Lutheran High Northeast on Thursday, March 14, 2019, in Norfolk. The school was being used as an evacuation shelter for people affected by flooding in the area.
Motorists are forced to turn around as West Maple Road west of 216th Street is closed as floodwaters rise over the road near the Elkhorn River in Elkhorn, Nebraska, Friday, March 15, 2019.
A crowd of people gather to overlook the floodwaters which continue to rise along the Missouri River in Plattsmouth, Nebraska, Friday, March 15, 2019.
Homes, vehicles and RV's are submerged in floodwaters that continue to rise along the Missouri River in Plattsmouth, Nebraska, Friday, March 15, 2019.
Adam Jensen races to load his Lincoln Navigator outside his home near Mayne and Condron Streets in Valley, Nebraska. With three kids and a dog they plan to head to a hotel in Iowa. Valley residents were ordered to evacuate because of flooding on Friday, March 15, 2019.
CJ Cunningham holds his German shorthair Cazz after they were rescued from the King Lake area Friday, March 15, 2019.
Water flows over Highway 30 between Fremont and Arlington, Nebraska on March 15.
People keep an eye on floodwaters along Highway 30 between Fremont and Arlington, Nebraska on Friday, March 15, 2019.
Horses belonging to Faye Etherington are brought into town through floodwater on Highway 77 in Fremont Nebraska on Friday, March 15, 2019.
Paul Schmidt walks with his children Calvin and Avery while looking back at floodwaters over Broad Street in Fremont Nebraska on Friday, March 15, 2019.
At sunrise, Norfolk City Engineer Steven Rames inspects the levy next to the Northeast Community College on Friday, March 15, 2019, in Norfolk, Nebraska. Rames said the levy was stable and that the water had dropped 8 to 9 feet.
A pickup is stranded on the east side of Norfolk, Nebraska, in floodwaters on Friday, March 15, 2019.
Sarpy County Sheriff’s Deputy Darin Morrissey rides an ATV through floodwaters in Hawaiian Village on this date a year ago.
Ron Eklund looks east at a flooded Main Street on the eastern edge of Plattsmouth on March 16.