a climate scientist at washington state university vancouver. thanks for joining us.hat is dry lightning? why is it dangerous, in terms of sparking wildfires? >> dry lightning is essentially regular lightning but occurring with a very little -- with very little rainfall. sometimes no rainfall at all. you have lightning hitting the ground, possibly hitting dry vegetation, then no rain to follow or not enough rain to follow to put out that fire. kristen: i see. which of our recent wildfires in california were started by dry lightning? >> a lot of the fires in 2020. you might remember in august 2020, california had that big lightning storm at around this time mid month. the wildfires burned several million acres and killed dozens of people. kristen: the study mentions the widely accepted definition of dry lightning doesn't quite capture the full risk. can you elaborate? >> yes, of course. typically, this dry lightning phenomenon is defined by saying it's going to be lightning with less than 1/10 of an inch of rain. if there is less than 1/10 of an inch of rain, it means