Marathons: global warming casualty?

This past weekend's Chicago Marathon was only the latest to fall apart due to unseasonably high temperatures, though it did fall apart fantastically. It was 70 degrees at the 8 AM start--quite warm, but not impossible--but by 11:30, temperatures had hit the high 80s. Runners were collapsing, calling 911, and flooding aid stations in distress, and officials stopped the race. (This means the elite runners were all in, but many, many runners did not get to finish the race.) Worse yet, one man died during the race. (NYT)

Here in DC, there was also tragedy at the Army Ten-Miler that day. One runner died in the 80-degree, 94-percent-humidity conditions. (WP)

No one wants to bag a race after training for months and dropping a lot of money on travel and lodging. But after the bad experiences in Chicago, and in London earlier this year, I wonder whether more runners will think twice during the freak heat waves, cold snaps, and storms that are becoming more and more common.