Rick Thoman~Atmospheric River~South Central Alaska

Today's episode includes an interview with climate specialist, Rick Thoman. Rick discusses the conditions that lead to an atmospheric river, La Nina winter predictions and also the importance of weather forecasts and radio coverage for Alaskans. 

Rick Thoman, a climate specialist at IARC’s Alaska Center for Climate Assessment and Policy (ACCAP).  Rick is a contributor and editor of the Arctic Report Card and was also awarded NOAA Distinguished Career Award for Professional Achievement in 2020. Rick was honored after a 30 plus year career with the National Weather Service for continued efforts to improve climate services in Alaska and for outstanding outreach efforts working with the Alaska Native community. We are happy that he has not yet retired, as his wealth of information is an invaluable resource for communities all around Alaska. Thank you, Rick!

Rick Thoman has a very informative newsletter on Substack called: Alaska and Arctic Climate Newsletter. You can see illustrations, graphs and be informed of all things Alaska weather.

Talkeetna River at Alaska Railroad Bridge NOAA link: 

 https://water.noaa.gov/gauges/TKTA2

Thank you for tuning into the Alaska Climate & Aviation Podcast!

Also, I'm happy to announce my scenic flight seeing business, Visionary Adventures, LLC.  "Cub Rides with Katie" offers scenic flights in a Piper Super Cub Airplane here in South Central Alaska.  Message me if you wish to book a flight. 

Katie Writer

ktphotowork@gmail.com

907/873-7669

Transcript

SPEAKER_00: 0:00

Well,

SPEAKER_01: 0:12

good morning, Rick. We've got Rick Thoman as our guest today for the Alaska Climate and Aviation Podcast. How are you doing today, Rick?

SPEAKER_00: 0:20

I'm doing great, Katie. Thanks for having me on again.

SPEAKER_01: 0:23

Oh, it's always wonderful to get a word from Rick. And we know that there is a lot going on in the weather with this fall. Right now in the south central Alaska, when you look at the weather report on the National Weather Service, there's a flood warning. And when you look at the satellite image, there's the atmospheric river coming in. Tell us a little bit about what your perspective is on this atmospheric river.

UNKNOWN: 0:50

Thank you.

SPEAKER_00: 0:51

Yeah, so atmospheric rivers, it started out as a jargon term within the meteorological community. It's been around since the 1990s. But it's really, in the last 10 years or so, really come into public awareness, been picked up by the media, social media. And there's good reason for that, because atmospheric rivers are an important mechanism for delivering precipitation to many parts of the world. of the world, but especially the Pacific coast of North America, which includes Alaska. However, I think it's fair to say that atmospheric river, perhaps like the polar vortex, is one of those terms that many people have heard, but don't really have a good idea of what it actually means. And so from the meteorological perspective, an atmospheric river is just typically a very narrow but elongated area with very high moisture and winds so that that high moisture is being moved along rapidly. So we're talking large scale here. Atmospheric rivers are typically thousands of miles along. They typically originate over the oceanic areas. And they are really important because basically they are moving moisture and heat from lower lattice to higher latitudes. So if you think of the kind of the classic Pineapple Express for California, you know, you can see on the satellite pictures this area of enhanced clouds extending from near the Hawaiian Islands all the way to the California coast. So that's that northward movement of that moisture and that subtropical air. Same thing, of course, happens in Alaska. Atmospheric rivers are a major source of extreme precipitation for southeast Alaska. They have been the causative weather features for some of the terrible, tragic landslides that we've had in Alaska in the last five years. But they are also important for actually most of the state, with maybe the exception of the North Slope, because Alaska is really just one big fat peninsula in northwest North America. So even areas that we think of inland, like Talkeetna, like interior Alaska, we're actually not that far away from saltwater. And so we see these regularly, these atmospheric rivers regularly produce very high precipitation levels. often with high impacts. So just this week, we have had at least three different atmospheric rivers impact Alaska. The first one impacted northern interior into the Fairbanks area, producing in Fairbanks the highest August rainstorm in six years since 2019, brought some rivers up close to flood stage. Another atmospheric river impacted western Alaska, produced in some areas rainfall amounts that are in that, you know, the famous one in a hundred year level. And now the most recent atmospheric river really hitting south central. Some places like Halkitna, upper Susitna Valley, have gotten a lot of rain out of this. Other places like the immediate Anchorage area got some rain, but also a lot of wind. And that's the result of that very moist, very warm air coming across the mountains and downsloping. So a whole variety of weather. Now, the situation this week actually has been quite interesting in the sense that much of the state has gotten significant rain from these atmospheric rivers. But the place that you expected to be rainy at the end of August, southeast, is enjoying day after day of sunshine. And in some place there's actually been the temperatures of the entire summer have been this week in southeast

SPEAKER_01: 5:17

oh gosh well those people are lucky to get a little bit of that sunshine before uh the upcoming fall turns into winter pretty quickly around here so good for them they deserve that sunshine well it's nice that you've uh you mentioned the pineapple express i see you've got your hawaiian shirt on today for fridays in the office

SPEAKER_00: 5:38

yep absolutely

SPEAKER_01: 5:38

that's good to keep keep a smile on your face And yeah, we're the look of, you know, this is what we have. We have a lot of rain just sitting here in Talkeetna. There's been gusty winds, definitely some branches here and there. And I walked down to our local river here at the Talkeetna River and it's bank full. Yeah,

SPEAKER_00: 6:00

there's certainly been a lot of rain. And when we get these high amounts of rain in relatively short times, 12 to 24 hours, that the atmospheric rivers deliver, that's, of course, a recipe for big rises on rivers because the ground gets rapidly saturated and you got a lot of rain running into the rivers in short order.

SPEAKER_01: 6:21

Yeah. Well, you said, you know, here we have smack dab in the middle of hunting season. And so there's a lot of... People out hunting, and I'm sure they're getting their camps up, and it's not really flyable. So people are hunkering down. When would you expect this system to taper off?

SPEAKER_00: 6:41

Well, that is a good question. So the third of our atmospheric rivers is moving out as we speak here on Friday. But we may not be done, especially in the western half of the state. Looks like we've got another round of at least some storminess, maybe another atmospheric river farther to the east. We've got a couple of cool days gone up here, but then the warm air is going to return. So hopefully things overall are going to improve at least by late in the weekend and early next week. But certainly we're at that time of year. It's getting dark again at night, and so the atmosphere is cooling off. And with all this rain, that means there's a lot of low-level moisture around. So we're at the time of year, of course, where even if the large-scale weather is good, it can certainly be foggy in overnight hours and right into the morning. So it can limit the amount of time, for instance, that folks can fly.

SPEAKER_01: 7:41

Yeah, well, it sounds a lot like Alaska, doesn't it?

SPEAKER_00: 7:46

Sounds like autumn in Alaska,

SPEAKER_01: 7:48

absolutely. Yeah. Well, for thinking forward thinking, I noticed there's some talk about a La Nina winter. Do you want to talk a little bit about that?

SPEAKER_00: 8:00

Sure. So last year, we had kind of a dud La Nina winter. It tried and actually did meet the criteria for La Nina for just a couple of months, and it was very weak. And so we're going to try again this winter, or the ocean atmosphere is going to try again this winter. The forecast from the Climate Prediction Center is for this also to be a short-lived and weak La Nina event. Now, remember, La Nina is really an enhancement of the typical trade winds and and thunderstorm patterns in the equatorial Pacific, whereas El Nino is kind of a reversal of that. So La Nina is just kind of the Pacific tropical atmosphere boosted up a little bit. Now, the definition of La Nina is in a region close to the equator, south and southeast of Hawaii, to have the average sea surface temperature at least a half a degree below normal. And of course, a very common question is how can a sea surface temperature half a degree below normal, a thousand miles southeast of Hawaii, how can that possibly affect our weather? Great question. And the answer is that that little tiny temperature difference doesn't affect our weather. But it does affect where those big giant tropical thunderstorms along the equator form and are sustained. And it's through those big tropical thunderstorms which in turn affect the jet stream farther north, that's the connection to our weather. It's how those big thunderstorms are modified, where they persist, where they don't persist, and they in turn affect the winds aloft much farther north and can put their imprint on the seasonal scale weather pattern.

SPEAKER_01: 10:06

Okay, well, that's a good explanation there. And people are looking at... you know, how to prepare for the winter mentally. And so it's good to have that little tip. So it's not certain that there'll be a lot of snowfall, but those La Niñas can provide a lot of moisture. And if the temperatures are low enough, it's snow. And if the temperatures are warmer, then it's rain.

SPEAKER_00: 10:30

Yeah. And, you know, we had this weak La Nina last year. And of course, especially in South Central, in some places there was like no snow or hardly any snow, at least during the core winter. But really, last winter was really interesting from the climate perspective in the sense that low elevation. So let's say low elevation Anchorage had very little snow, no measurable snow on the ground the entire month of February. First time that's ever happen. But you go up, 2,000 feet in elevation on the hillside, there was plenty of snow. And that's a different scenario than we saw, say, during the 2015-16 winter when there was very little snow in urban Anchorage, but there was also very little snow in the mountains, just didn't precipitate. Last winter, it wasn't a matter of we didn't have the precipitation. It was that at low elevations, it was just warm enough that it was rain. Saw the same thing in the Talkeetna Mountains as well with much relative to normal, much closer to normal or even above normal snowpack at higher elevation near or below normal snowpack at the low elevations. And that's a function of temperature when that precipitation falls. Could that happen again this year? Sure, it could, especially with a weak La Nina. It really is only a weak push to the weather system. odds are, given that, for instance, Anchorage has not had a February with every day with no measurable snow on the ground, that's unlikely to be repeated just because it's a rare event and everything would have to come together in much the same way that the two winters before both featured big snowstorms. That's just the variation of the weather. A lot of pieces have to come together all at the same time in the right sequence and the right timing to get either big snowstorms or no snowstorms.

SPEAKER_01: 12:40

A lot of it is looking out the window that day and see what happens, and there you go. But we have a real reliance on weather services, and I understand that with our budget cuts in the national weather system, it's put a lot of people jobs feeling vicariously on edge. Tell us a little bit about, you know, as a longtime weather person like yourself, your relationships with some of the rural areas in Alaska throughout the state on how this impacts these communities. In addition to the radio cuts with, you know, the ability for weathermen to be able to talk to journalists to get warnings out for people and how these budget cuts impacted these communities in Alaska, maybe more than other parts of the nation.

SPEAKER_00: 13:34

Well, I think, Katie, that here in Alaska, what's the saying? Weather is not small talk in Alaska. Weather matters. It matters for our lives, our livelihoods, and in more cases than I think in the lower 48, weather involves health, safety, life, and death decisions. So the services, the information critical for Alaskans, from big business to individuals. And having the loss of weather services, the estimate is about 10% of the people that were employed by the weather service in Alaska in January have left. And while the weather service is is now attempting to rehire and fill some of the vacancies that were created, whether through voluntary departures or involuntary departures. That hasn't happened yet. So we have a lot fewer people within the National Weather Service being able to provide services. The Fairbanks office just ended part-time operations. They've gone back to 24 hours a day, but they were reduced to no overnight shift most of the summer. Fairbanks had been a 24-hour day, seven-day-a-week forecast office from the early 1970s until the summer, and that was entirely a staffing issue. It simply didn't have the number of human beings on staff to do it. And so Fairbanks, for instance, has forecast responsibility for the entire state north of the Alaska Range and out to western Alaska, including the entire Yukon Delta and everywhere north of there. So a large area, forecasts were being sent out from the Anchorage office, so those forecasts were there, but you didn't have people with experience in the regional weather, in the regional specifics, working those forecasts. At the same time, as you mentioned, the threat to radio in rural Alaska is really an existential threat. Unlike Anchorage, unlike Fairbanks, as well as, of course, most places in the lower 48, in rural Alaska, generally, there is no other option. If your public radio station goes away, you have no radio because you've got a choice of one. Some communities like Nome are lucky to have two, but if that programming or the stations even have to go off the air, that would be a major impact. And as we're seeing already, maybe they don't go off the air completely. Maybe they don't. Maybe they're closed overnight. And okay, weather doesn't work on a clock, right? Warnings go out at 3 a.m. if there's no radio station to get that out. How are you going to get that given the difficulty and frequent unreliability of things like cell service in rural Alaska? So There's a lot, a lot of negative impacts to really helping people be safe and to be efficient in their day-to-day lives. And I hope that we can find a way to get back some of this so that Alaskans have access to the best information in making decisions.

SPEAKER_01: 17:27

Well said, Rick. That really does summarize the incredible dependence on radio. And people have so much more exposure here in Alaska. And we are really grateful for you and all your expertise that you share. And also, a lot of journalists are going to different resources of ways to get information out, such as, you know, even my podcast, Alaska Climate and Aviation Podcast. More journalists are popping up ways in newsletters. For example, your newsletter. Do you want to tell our listeners about how they can learn how to get in tune to your newsletter, how they can subscribe to it?

SPEAKER_00: 18:14

Sure. So I write the Alaska and Arctic Climate Newsletter. And this is, it's completely free It is on Substack and so anyone can subscribe to it and it won't cost you a dime. And I try to provide a mix of what's happening now in Alaska and the Arctic. So some of the posts are, you know, kind of a larger scale, but focused on the Arctic. Some of them are specific to Alaska. My most recent one was about the importance of atmospheric rivers to mainland Alaska, as we've seen this week. Of course, that's what prompted that. So it's completely free. There's usually put out one a week or a little less. And so if folks are interested in keeping abreast of what's happening at the monthly to seasonal scale in Alaska and the Arctic, as well as various topics related to particularly climate, it's not a weather forecast service, but rather a climate scale focus. And so if you're interested in things like long-term trends or just keeping up on the month-to-month, season-to-season weather, it's a free and easy resource that I hope is written in a way that people, without being experts, can get the information they need. Always have lots of graphics in there. And so I appreciate feedback on those. And if folks are interested, allow and Arctic climate newsletter on Substack.

SPEAKER_01: 19:55

Great. Well, I'll put the link in on the written portion of the podcast so people can just click on that link and sign up. I enjoy your newsletters greatly. And another continual long-time project that you have done is the Arctic Report Card. Do you have any comments about what's going to be coming up with this year's report card?

SPEAKER_00: 20:18

Yeah. So, yes, I I have been actually a contributor, an author for the Arctic Report Card for a decade now, and I've been one of the general editors of the Report Card. This will be the sixth year I've served in that role. And, of course, the Arctic Report Card is basically supported by NOAA, although it is not a report on NOAA activities in the Arctic. Obviously, we had some concerns. Would we be able to do the report? card this year? And the answer I'm happy to say is yes. This will be the 20th edition of the Arctic Report card. First one came out in 2006. So this will be number 20, come out every year. And so we've got several fun extras for this year where there's a photo contest underway right now. So you can win your 15 minutes of fame and fortune with that. And we'll have our usual review of what's happened in the last year in the Arctic, both from the physical science side, so the usual things like how have temperatures been in the past year, sea ice, ocean temperatures, as well as a couple of contributions on fisheries. In Alaska, I think that will be a high interest one. And we've also got a contribution coming from from the Indigenous Sentinels Network based out of the Pribilof Islands, which will be, I think, another very high-interest topic for folks, especially in Alaska, on the work that the network is doing.

SPEAKER_01: 22:07

Fantastic. Well, we've really appreciated all the past episodes that we've done every year on the Arctic Report Card, so I'll tell our listeners we'll definitely be having another one set up for this January for seeing what's been going on in the state and also all around the Arctic countries. Well, very good, Rick. Well, this has been a wonderful time to catch up with you and hear about the going on and hear about your newsletter as well as knowing that there will be an Arctic Report card. And we so appreciate your dedication as being the voice of weather here in Alaska. And we wish you a wonderful rest of your weekend.

SPEAKER_00: 22:50

Great. Thanks very much, Katie. And stay dry.

SPEAKER_01: 22:56

And that concludes today's episode of the Alaska Climate and Aviation Podcast. I'm Katie Ryder. Today is August 29th. Wishing you all a happy Friday and happy Labor Day weekend.