I found a link to this story on Aquafornia this morning and was intrigued enough to read the article - even though I was skeptical. Obviously the first thing that jumps out at you is the title - "Watering fields in California boosts rainfall in Southwest". Makes you think that someone has possibly confirmed a link between the two. But then you read the first line in the story and that claim is qualified with "a new computer simulation suggests." So it turns out that using an appropriately scaled atmospheric circulation model and making some assumptions about excess evaporation occurring in the Central Valley of California in the summer it appears it just might be possible that some of the summer thunderstorms over the southwest could be modestly enhanced by said excess evaporation.
It sounds like they may have a good idea for some more detailed study. It doesn't sound like they showed a clear link between the two occurrences. But if you click through to the article, go to the bottom where you can access the paper by Jay Famiglietti at UC-Irvine on which the article is based. I haven't read the whole thing yet but it appears to discuss their research as preliminary but with promising results for additional study - especially because it could have ramifications for modelling future flow scenarios on the Colorado River. It's also possible that this interaction is simply too complex to be reliably modeled, but hey, let's give it a chance.
This also makes me think of another article I saw today from Circle of Blue discussing the general, widespread failure of journalists to accurately portray the significance of water issues - especially the nature of uncertainty. If we want people engaged in policy-making that can significantly affect their lives they need to understand the issues. That means someone needs to adequately explain them. I had a subscription to Science News for a while when I was younger but
generally found their articles to be shallow and not always very well
written. Looks like nothing has changed.