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Observing Alaska Lake and River Freeze-Up Through Fresh Eyes on Ice

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Observing Alaska Lake and River Freeze-Up Through Fresh Eyes on Ice Observing Alaska Lake and River Freeze-up through Fresh Eyes on Ice Chris Dana Laura Katie Arp Brown Oxtoby Spellman Hydrologist Geographer Ecologist & Ecologist & Educator Educator Kuskokwim River above Kwethluk 1819223141727710-NovDec-OctNovDec-2019--20192019 14-Oct-2019 FirstskimpanHalloweenNewMostlyBeringGradualAnotherComplete-ice -iceObservationice Seacovered forming refreezemeltformingaccumulating refreeze warmstorm event withand -episodeand upbringof-up! accumulatingIcejumbled snowfall another ice melt event Outline of Webinar 1. Overview of Fresh Eyes on Ice – a new freshwater ice observation network for Alaska 2. Freeze-up process: what it signals and why it matters 3. River and lake freeze-up at global to local scales 4. This year’s freeze up in context of past 5. Community and citizen science observations of freeze-up Connecting Arctic Communities through a Revitalized and Modernized Freshwater Ice Observation Network Investigators Chris Arp Dana Brown Laura Oxtoby Katie Spellman Team Members Karin Bodony Allen Bondurant Sarah Clement Melanie Engram Tohru Saito Theresa Villano Peter Webley Collaborators Alaska DNR (Parks and ADF&G) Bethel Search & Rescue NNA/AON USFWS, NPS, and BLM #1836523 River Watch Program (NOAA) (2019 – 2024) … and many Alaska communities http://fresheyesonice.org/ & schools Connecting a Landscape of Water and People through Observations Surveys & Field Studies Remote Sensing Real-time Cameras & Ice Buoys Archiving & Analysis of Historic Data Community-based Monitoring & Science Education Learning from our Elders Elder Sam Demientieff (Holy Cross/Fairbanks) sharing knowledge of changing ice and much more Learning from the past Observing the present Shaping the future. Community Based Monitoring Teams 2019-20 Noatak Shageluk Fairbanks Venetie Bethel Galena New this year: Kenny Lake, Tok, Anderson, McGrath, Nenana, Kobuk, Arctic Village, maybe others! Getting youth outdoors observing their environment Developing STEM skills & confidence Collaborating with community members, educators and scientists to create a dataset for community safety, planning, science, and learning Sharing freeze-up & break-up observations across the state Kuskokwim River above Kwethluk 30-Jan-2020 Freeze-up process: what it signals and why it matters Ice Types & Freeze-up on Lakes wind-storm broken and refrozen ice pan black ice (congelation ice) white ice (snow ice) Teshekpuk Lake - April 2016 Profile of Freeze-up in a River Pan or Pancake Ice (photo by Edmond Perkins) From Lindenschmidt 2020 in River Ice Processes and Ice Flood Forecasting Magnuson et al. 2000 Science Recorded as first day water body totally ice covered Observations made by people before direct scientific observation programs of ice (and climate in many areas) 6 day earlier freeze-up / 100 yrs translates to 1.2⁰C increase air temperature / 100 yrs Freeze-up can be a long process! How do we decide which day it happened on and does the rest of the freeze period matter? Examples of Freeze-up Sequence from Yukon River near Grayling (Landsat) “Safe for person “Unsafe for “Unsafe for on foot ” boat” (?) boat” “Safe for “Safe for person on snowmachine” “Unsafe for “Unsafe for foot” (?) “Safe for person on person on snowmachine” foot” foot” (?) From Brown et al. 2018 & NWS Alaska Pacific River Forecast Center Common View of Alaska from Optical Satellites (e.g. Landsat) in Winter makes Remote Sensing of Freeze-up Challenging! Example of Detecting Open-water areas on Kuskokwim River using Satellite Radar & Nov. 18, 2019 Aircraft Photos Backscatter (dB) 2 to 4 0 to 2 0 to -2 -2 to -4 -4 to -6 -6 to -7 -7 to -8 -8 to -9 -9 to -10 -10 to -11 -11 to -12 -12 to -13 -13 to -14 -14 to -15 -15 to -16 -16 to -17 -17 to -18 -18 to -19 -19 to -20 -20 to -24 Photo from Charles Guest (Bethel -24 to -28 -28 to -32 Nov. 24, 7:25 pm local Search and Rescue) -32 to -36 -36 to -40 Sentinel-2 C-band VV Synthetic <-40 Aperture Radar (SAR) Engram et al. in progress Satellite radar can image in dark & through clouds, but hard to interpret without ground-truth data! Freeze-up timing and state in relation to how people use rivers Kuskokwim River freeze-up causes complications for Bethel barge service By Greg Kim, KYUK - Bethel - November 7, 2019 Bethel Boat Harbor on Nov. 13, 2014. (Photo by Dean Swope) …[barge] company’s issues are due to the unpredictable freezing, thawing, and refreezing of the ice. …late freeze up this year (2019), some barge companies are trying to squeeze in some final trips. Other river uses dependent on freeze-up sequence: 1. Ice-fishing / gillnetting 2. Hunting & trapping 3. Inter-village travel 4. Ice road construction 5. Others ? River use during early winter probably highly dependent on river and region, level of caution / comfort, and level of knowledge of ice and the river River and Lake Freeze-up at Global to Local Scales Tanana River below Fairbanks November 2019 Shift from lakes with reliable ice every winter to ice in some years, but not others Sharma et al. 2019 Nature Climate Change River ice cover duration declined from 1984 to 2019 and projected to continue to 2100 Yang et al. 2020 Nature Trends in freeze-up date based on local observations Trend towards later freeze-up Brown et al. 2018 Weather, Climate, and Society Changing river ice seasonality and impacts on interior Alaska communities Changes in October air temperature cooler warmer Brown et al. 2018 Weather, Climate, and Society Changing river ice seasonality and impacts on interior Alaska communities Kuskokwim River at Bethel 15-Dec 5-Dec 25-Nov Observations 15-Nov First Ice Freeze-up 5-Nov Unsafe for Boats Safe for People 26-Oct Safe for Snowmachine 16-Oct 6-Oct 26-Sep 1959 1969 1979 1989 1999 2009 2019 Kuskokwim River above Kwethluk 1819223141727710-NovDec-OctNovDec-2019--20192019 14-Oct-2019 FirstskimpanHalloweenNewMostlyBeringGradualAnotherComplete-ice -iceObservationice Seacovered forming refreezemeltformingaccumulating refreeze warmstorm event withand -episodeand upbringof-up! accumulatingIcejumbled snowfall another ice melt event Colville River above Nuiqsut 7-Oct-2020 2020 Freeze-up in Context http://akclimate.org/ 20.0 Fairbanks, AK NWS data - 2019 15.0 15-Oct (Freeze Threshold Date – FTD) 10.0 50 F 5.0 0.0 32 F Ta - Mean Daily -5.0 Air Temperature (⁰C) Air Temperature -10.0 16 F Ta - 31day-centered- -15.0 running-mean -20.0 28-Aug 12-Sep 27-Sep 12-Oct 27-Oct 11-Nov 26-Nov Reference Period (1980-2010) Last Year (2019) This Year (2020)* What does Freezing Threshold Date mean for ice and people using it? Example from NWS Alaska River Forecast Center data 35 on Kuskokwim River in Bethel based on 30 intermittent records since 1960 lots of variation among years! 25 20 very high Threshold Date Date Threshold year-to-year 15 variation 10 5 Days after Freeze Freeze after Days 0 First Ice Freeze-up No Boats Safe for People Safe for Vehicle (mixed type) Freeze Utqiagvik 14-Sep Threshold 29-sep 7-Oct Date 1980 – 2010 2019 2020 Kotzebue 4-Oct Bettles 28-Sep 13-Oct 18-Oct 4-Oct 28-Sep 6-Oct Fairbanks 15-Oct 11-Oct 18-Oct Talkeetna 16-Nov 18-Oct Bethel 13-Oct Anchorage 22-Oct 20-Oct 20-Oct 23-Oct 30-Nov http://fresheyesonice.org/realtime-data/ Allen B. modeling ice buoy Colville River above Nuiqsut 7-Nov-2020 Lake Ice Thickness ~ 35 cm (14 in) Noatak River below Noatak 7-Nov-2020 Lake Ice Thickness ~ 22 cm (9 in) Innoko River below Shageluk 8-Nov-2020 Lake Ice Thickness ~ 10 cm (3 in) Yukon River at Galena 8-Nov-2020 Lake Ice Thickness = 23 cm (9 in) on 2-Nov Yukon River below Holy Cross 9-Nov-2020 Lake Ice Thickness ~ 15 cm (6 in) Kuskokwim River above Napaskiak 9-Nov-2020 Lake Ice Thickness ~ 5 cm (2 in) Kantishna River above Tanana River 9-Nov-2020 Lake Ice Thickness ~ 15 cm (6 in) Copper River below Tazlina River 8-Nov-2020 Lake Ice Thickness – 10 cm (4 in) Ways to report observations: Your observations matter • Fresh Eyes on Ice Photo Portal • NWS River Watch Form How can you contribute this freeze-up season? • LEO Post • Fresh Eyes on Ice Facebook fresheyesonice.org Ways to report freeze-up observations 1 UAF Fresh Eyes on Ice Photo Observation Portal Fresheyesonice.org Ways to report freeze-up observations 2 NWS River Watch https://www.weather.gov/aprFc/RiverWatchProgram Ways to report freeze-up observations LEO Network Post 3 https://www.leonetwork.org/ Ways to report freeze-up observations 4 Join Fresh Eyes on Ice Facebook group Thank you! Chris Arp UAF Water and Environmental Research Center [email protected] Laura Oxtoby UAF Institute of Northern Engineering [email protected] Dana Brown Institute of Arctic Biology [email protected] Katie Spellman International Arctic Research Center 19-Oct Smith Lake [email protected].
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