An atmospheric scientist at Iowa State University says the conventional wisdom in the scientific community is that severe weather events like this weekend’s storms in Iowa are caused by global warming. But I-S-U’s Gene Takle says such “extreme” weather events as deluges of rain have happened “with some regularity” in the past. Takle says to put it in perspective, there were daily rain totals of nine inches in many Iowa locations during 1993, when there was major flooding. However, he says “it’s not unreasonable” to think there will be more frequent “extreme” weather events in the future. Takle says it is a bit unusual for a storm system to spawn so many tornadoes.But Takle says the record is probably held by a 1974 storm system in Ohio that spawned 600 tornadoes over a 36 hour period. Takle says as I-S-U weather experts gather around the water cooler today, most are talking about drying out their basements, as Ames received a dumping of rain that prompted flooding over the weekend.