In 2005, Sperry Glacier in Montana was added to the program, allowing changes in glacier mass in the principal North American climate zones to be tracked. Systematic errors accumulate through time in this method; Measurements began on South Cascade Glacier, WA in 1958, expanding to Gulkana and Wolverine glaciers, AK in 1966, and later Sperry Glacier, MT in 2005. This map is of the same glacier depicted in the photos attached later in the lesson. 2Methods 2.1 Site description The USGS began consistent measurements of glacier mass balance, streamflow and meteo-rology at Gulkana and Wolverine glaciers in 1966. S. O'Neel is acknowledged for providing the Gulkana Glacier mass balances, M. Huss for the Black Rapids ice thicknesses, and A. Arendt for computational resources and funding. 3 1. Episodes of positive glacier-wide mass balance (greater than uncertainty) have modulated mass loss at Wolverine Glacier several times since the observations began (Fig. Under the following links you find more information about the reference glaciers, the mass-balance datasets, and detailed assessments of global glacier mass changes.. 2 Mass balance data. Over the 1946–2018 period, the cumulative mass balances diverged. Camping trip to Gulkana Glacier. (Liljedahl et al., 2017). For each glacier, the mass balance is set at zero for the base year of 1965. Will the glacier grow, or shrink? The net mass balance on Gulkana Glacier, Alaska, U.S.A., has been measured since 1966 by the glaciological method, in which seasonal balances are measured at three index sites and extrapolated over large areas of the glacier. Mass balance, meteorology, area altitude distribution, glacier-surface altitude, ice motion, terminus position, and runoff at Gulkana Glacier, Alaska, 1996 Balance Year. Analyse the Glacier Mass Balance Over the whole time period, is the average annual mass balance (Ba) positive or negative? Measurements began on South Cascade Glacier, WA in 1958, expanding to Gulkana and Wolverine glaciers, AK in 1966, and later Sperry Glacier, MT in 2005. C. Ice motion also slowed, which combined with the negative mass balance, resulted in glacier retreat under a warming climate. [Rod March; Geological Survey (U.S.)] Validation of Glacier Mass Balance Modeling Using USGS Measurements [11] The PTAA model uses the bias-reduced MM5-down-scalings (daily maximum and minimum temperatures and precipitation) as inputs in combination with the area altitude distribution of Gulkana Glacier to simulate the Gulkana Glacier mass balances. Using data for the last 10 years and the first 10 years of the dataset, calculate the average annual glacier-wide mass balance … 2.1 Mass Balance Observations. Since the late 1950s, the USGS has maintained a long-term glacier mass-balance program at three North American glaciers. Systematic errors can accumulate linearly with time in this method. Mass balance (m w. eq.) Vertical photographs were taken on August 31, 1967, by Austin Post and were used to redefine the margin of Gulkana Glacier and other glaciers and perennial snow fields in the basin. 4A) was relocated at 2,020-m altitude in the eastern cirque of Gulkana Glacier. The Jarvis Glacier is located north of the Gulkana Glacier; a drilling project was conducted on the glacier in April 2017 (Miner et al., 2018). Mass balance is typically calculated over a balance year, which begins at the onset of snow and ice accumulation. This figure shows the cumulative mass balance of the three U.S. Geological Survey “benchmark” glaciers since measurements began in the 1950s or 1960s. The focus is on modeling mass balance and discharge of the Gulkana Glacier in Alaska and applying a climate change scenario in order to determine the magnitude of the effects of climate change on the Gulkana glacier and how the melt water will contribute to total sea level rise. Tuesday, August 3, 2010. The Gulkana Glacier is one of three benchmark glaciers in the United States that the US Geological Survey have been monitoring since 1971. how glacier mass balance processes impact streamflow, ultimately improving our conceptual understanding of the future evolution of glacier runoff in continental and maritime climates. water balance of Gulkana and Woverine Glaciers, Alaska, and South Cascade Glacier, Washington, 1965 and 1966 water years. Gulkana Glacier is a multi-branched valley glacier located in a continental climate regime on the south flank of the eastern Alaska Range in central Alaska. This paper presents a brief review of the glacier mass balance status and their analysis under the changing climate in the Indian Himalayan Region (IHR). At Gulkana Glacier, sustained negative mass balance has been associated with substantial area loss. The “mass balance” of the Gulkana has been calculated at different times in an ongoing study about the effects of our dependence on fossil fuels and the related global warming crisis. Thus, the balance year beginning in September 2013 and ending in September 2014 is called “balance year 2014.” USGS began biannual measurements of glacier mass balance and meteorology at Alaska's Wolverine and Gulkana glaciers in … Glacier mass balance is the direct and non delayed response against the climate change and hence it is one of the essential variables require to monitor the climate system. Negative values indicate a net loss of ice and snow compared with the base year. Measurements began on South Cascade Glacier, WA in 1958, expanding to Gulkana and Wolverine glaciers, AK in 1966, and later Sperry Glacier, MT in 2005. Direct field measurements are combined with weather data and imagery analyses to estimate the seasonal and annual mass balance at each glacier in both a conventional and reference surface format (Cogley and … Table 2: Reported mass balance values of the observation period 2017/18, 2018/19 as well as *preliminary values for 2019/20. Mass Balance Factsheet for the Gulkana Glacier, Alaska. Since the late 1950s, USGS has maintained a long-term glacier mass-balance program at three North American glaciers. Results from South Cascade Glacier in Washington and Gulkana and Wolverine glaciers in Alaska provide the longest continuous record of North American glacier mass balance. Explaining mass balance and retreat dichotomies at Taku and Lemon Creek Glaciers, Alaska. What does this mean for the glacier? 3.2. We reanalyzed mass balance records at Taku and Lemon Creek Glaciers to better understand the relative roles of hypsometry, local climate and dynamics as mass balance drivers. During 1997-2001, Gulkana Glacier showed a continued and accelerated negative mass balance trend, especially below the equilibrium line altitude where thinning was pronounced. Systematic errors can accumulate linearly with time in this method. The net mass balance on Gulkana Glacier, Alaska, U.S.A., has been measured since 1966 by the glaciological method, in which seasonal balances are measured at three index sites and extrapolated over large areas of the glacier. Since the late 1950s, the USGS has maintained a long-term glacier mass-balance program at three North American glaciers. of the Gulkana Glacier (from USGS database) Balance Year Winter Balance Summer Balance Net Balance 1966 0.93 1.03 -0.1 It is a polythermal glacier (Miner et al., 2018), and the mean annual mass balance during 2011–2016 was −1.6 m w. eq. ciers: Wolverine Glacier in Alaska’s Kenai Range, Gulkana Glacier in the Alaska Range, and South Cas-cade Glacier in Washington State’s Cascade Range (Fig. [2] A glacier with a sustained negative balance is out of equilibrium and will retreat, while one with a sustained positive balance is out of equilibrium and will advance. Since the late 1950s, the USGS has maintained a long-term glacier mass-balance program at three North American glaciers. It is imperative that we understand and quantify how this will affect freshwater river runoff and downstream hydrology in order to better inform local response, policy, and resource management. From 1980-2008 the mean cumulative mass loss of glaciers reporting mass balance to the World Glacier Monitoring Service is -12 m. This includes 19 consecutive years of negative mass balances. The trends of climate change indicate that glacier melt will continue to increase. K. Echelmeyer, M. Stuefer, and R. Flanders were instrumental in maintaining the mass balance program on Black Rapids Glacier during the 1990s and 2000s. 2016). Gulkana Glacier is located on the south side of the Alaska Range about 10 miles north of Paxson, along the Richardson Highway.