State climatologist: drought outlook ‘hasn’t been this good since the spring of 2019’

[MUSIC PLAYING] CATHY WURZER: An update on Minnesota's long-lasting drought came this morning, and the news is looking good. For the first time since 2020, the vast majority of Minnesota is no longer in a drought at all. That news comes just before Governor Walz is set to announce air quality forecasts for this summer at 2 o'clock this afternoon.

We're hoping the lack of drought means less wildfire and smoky air for the next few months. The end of the drought is also a huge relief to farmers statewide. For perspective on what this report means, we're joined by Luigi Romulo and Lindsay Pease. Luigi is the state climatologist, and Lindsay is a professor of nutrient and water management with the University of Minnesota. Welcome to you both.

LUIGI ROMOLO: Thank you, Cathy. Glad to be here.

LINDSAY PEASE: Yeah, thank you.

CATHY WURZER: And thank you. I appreciate your time, Professor Pease. Well Dr. Romolo, let's start with you. Good news, but does it mean that the drought is over?

LUIGI ROMOLO: It doesn't because a location is never really more vulnerable to drought than when it first comes out of drought. Now, we've had a lot of healthy precipitation, and what's been great about our precipitation is, we've got it in nickels and dimes, a little bit here, a little bit there. And we haven't lost a lot of it to runoff.

So our soils are starting to get full. Our lakes are boosting up. Most of our rivers, with the exception of some small areas in the upper Mississippi headwaters, are at or above normal flows. So we're in really good shape right now.

CATHY WURZER: When was the last time we were in a position as good as we are right now?

LUIGI ROMOLO: Probably when we came out of the 2021 drought in the spring of 2022. But I could make an argument that it hasn't been this good since probably the spring of 2019.

CATHY WURZER: Yeah, I was thinking about that, too. Professor, paint a picture of what this drought has meant to farmers over the past few years. They've been, I'm sure, so worried. Tell us kind of what they've been dealing with, if you would.

LINDSAY PEASE: Yes, so when you have a drought that just lasts so long, and farmers, their whole livelihood is based on that timeliness of rain. So it causes a lot of stress, a lot of worry, but it also puts a lot of pressure on other resources. You have to optimize everything because your water ends up limited.

So this is just such a big relief for farmers and really couldn't have come at a better time. I mean, the frost was out of the ground. The crops are just starting to come off. So I can imagine this being just a huge relief for most farmers around the state.

CATHY WURZER: A relief, but there's always a little bit of concern, right? Anything that they might be worried about in terms of soil and anything else that might pop up that could be a concern?

LINDSAY PEASE: Yes, of course you do get into that "when it rains, it pours." And when it pours, you have the potential for runoff, as Luigi mentioned. And so that's always a concern. It's like, well, especially when the crops are small, this is when they're really vulnerable to almost like a drownout because crops need oxygen, just like we do. But they get it from their roots and from the soil.

So when the soil is saturated, then they can't breathe. So then it becomes really important for that water to be able to move down. And again, coming out of the drought, there's a lot of space for that water to move down in the soil profile, but of course, these sporadic rains can make you nervous, too. Because 2020, we saw a lot of these repeat rainfall events that ended up causing more damage than good.

CATHY WURZER: I remember those. And Luigi Romolo, there are flash droughts that have occurred, too, right? So as you say, we're never more vulnerable when we're coming out of a drought. Things are looking good now, but do we know about the mechanisms that cause these flash droughts?

LUIGI ROMOLO: Yeah, so we get our precipitation in the spring from two primary sources. We get these low pressure systems that come out of Alberta, Canada, and they affect the whole state, but they control more of the precipitation in northern Minnesota. And additionally, we have a low pressure train that comes out of Colorado. And that affects the entire state, but controls more of the precipitation in southern Minnesota.

If one or both of those tracks get blocked by high pressure systems or there's semipermanent pressure patterns in the Eastern Pacific, like the Aleutian Low and the North Pacific High, when these shift or get stronger or weaker due to El Niño or La Nina, it can affect a drought here in Minnesota because it affects the tracks along which those lows move.

CATHY WURZER: While the beginning of a drought is difficult to determine, the end of a drought can occur as gradually as it started, I understand. So how will you know the drought is over completely? As a climatologist.

LUIGI ROMOLO: Yeah, as a climatologist, I would say once we've really kind of made a good comeback with some of the long-term precipitation deficits that we've seen over the past three years. So you could argue we've had three separate droughts in three consecutive years, or it's been one long drought that's waxed and waned. You look at some of the precipitation deficits over the last two years, and we're still anywhere from 6 to 8 to 10 inches below normal in some parts of the state.

But one can argue that while the soil doesn't hold all of that water, it can only hold a certain amount of water. And when it tries to hold more, it just percolates down into the ground or runs off into our lakes and streams. So once we start seeing our lakes and rivers back to normal, I would say that's when we're kind of-- and if our soils are also full of water, then that's when I'd say we're pretty much out of drought.

CATHY WURZER: OK. Say, last question to Professor Pease. Of course, as we were talking about this good news-- and it is at this point-- do farmers, do they have any way to mitigate any of these flash droughts that we have seen in the past few years?

LINDSAY PEASE: Well, one of the obvious ways that farmers-- and some farmers, especially more common in some parts of the state than others, is to use irrigation. And I will say that farmers, for the most part, are really also very concerned with groundwater resources and trying to conserve that. That's also when you're in a drought like that, how it becomes hard because is there enough to go around for everyone? But I will say, I think a lot of farmers do try to be very respectful and only take as much as they need. So irrigation is one way.

Another way that I like to talk about with farmers, especially in places where we start out with a lot of soil moisture, is to think about ideas like if they have subsurface drainage, you can actually kind of close off your drainage system using something called controlled drainage. And it's just all about conservation water management, kind of turning off your tiles if you do not need them to be running, but also conserving it to make it potentially available later on, things like sub-irrigation. Those are some of the strategies off the top of my head.

CATHY WURZER: OK. Because we're hoping that we will not have another flash drought again this summer. We have fingers and toes crossed that things are going to go back to normal as climatologist Luigi Romolo said to us. I appreciate the time from both of you, taking the time to talk with us. Thank you so much.

LUIGI ROMOLO: My pleasure.

LINDSAY PEASE: Yes, thanks for having us.

CATHY WURZER: And thank you, professor. That was the University of Minnesota Nutrient and Water Management Professor Lindsay Pease, along with state climatologist Luigi Romolo.