The 100th meridian is the longitudinal line running from Texas through Oklahoma, Kansas, Nebraska and into the Dakotas.
Climate experts designate this invisible line as the boundary line between the arid west and the more humid east.
A new study suggests climate change is expanding the desert eastward.
Richard Seeger, a professor at Columbia University, explains. Here's what else is on the show:
A climate voice: Kately Dorry. Katelyn, a 14-year-old student at Northern Lights Community School in Warba, Minn., talks about organizing a "Climate Convening" for members of her community, with the help of Youth Convening Minnesota.
A KARE 11 meteorologist returns from the Arctic. Sven Sundgaard talks about his recent travel to Svalbard, Norway — home to some of the summer's most unusual climate events. His stories about the trip will air this fall on KARE 11.