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. C. Over the 1946–2018 period, the cumulative mass balances diverged. During 1997-2001, Gulkana Glacier showed a continued and accelerated negative mass balance trend, especially below the equilibrium line altitude where thinning was pronounced. Ice motion also slowed, which combined with the negative mass balance, resulted in glacier retreat under a warming climate. Balance index station C (pl. 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. Thus, the balance year beginning in September 2013 and ending in September 2014 is called “balance year 2014.” 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. how glacier mass balance processes impact streamflow, ultimately improving our conceptual understanding of the future evolution of glacier runoff in continental and maritime climates. These glaciers have the longest continuous mass-balance records in North America, with winter balance B w, summer balance B s, and annual balance B a data available from 1959 to 2011 for South Cascade Glacier (World Glacier Monitoring Service 2012, 2013) and from 1966 to 2015 for Wolverine and Gulkana Glaciers (O’Neel et al. Examine the map of net mass balance for South Cascade Glacier in 1965. Camping trip to Gulkana Glacier. Get this from a library! 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. 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, meteorology, area altitude distribution, glacier-surface altitude, ice motion, terminus position, and runoff at Gulkana Glacier, Alaska, 1996 Balance Year. 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. 3 1. 4A) was relocated at 2,020-m altitude in the eastern cirque of Gulkana Glacier. 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. 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. (Liljedahl et al., 2017). 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. K. Echelmeyer, M. Stuefer, and R. Flanders were instrumental in maintaining the mass balance program on Black Rapids Glacier during the 1990s and 2000s. The Gulkana Glacier is one of three benchmark glaciers in the United States that the US Geological Survey have been monitoring since 1971. Tuesday, August 3, 2010. West Gulkana Glacier is located in the eastern Alaska Range, only 8 km east of the Richardson Highway and Isabel Pass. Mass balance is typically calculated over a balance year, which begins at the onset of snow and ice accumulation. Mass balance (m w. 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. 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. It is a polythermal glacier (Miner et al., 2018), and the mean annual mass balance during 2011–2016 was −1.6 m w. eq. 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 … Principal investigators are listed for submitted data of 2018/19. Will the glacier grow, or shrink? 1). 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). team of scientists remapped West Gulkana Glacier and determined its mass-balance changes. This map is of the same glacier depicted in the photos attached later in the lesson. Gulkana Glacier is located on the south side of the Alaska Range about 10 miles north of Paxson, along the Richardson Highway. 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. Negative values indicate a net loss of ice and snow compared with the base year. Analyse the Glacier Mass Balance Over the whole time period, is the average annual mass balance (Ba) positive or negative? Systematic errors can accumulate linearly with time in this method. [Rod March; Geological Survey (U.S.)] At Gulkana Glacier, sustained negative mass balance has been associated with substantial area loss. 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. 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 article summarizes the findings of this survey and reports on the inferences that the data permit for three decades of regional climate. eq.) water balance of Gulkana and Woverine Glaciers, Alaska, and South Cascade Glacier, Washington, 1965 and 1966 water years. Systematic errors accumulate through time in this method; Since the late 1950s, USGS has maintained a long-term glacier mass-balance program at three North American glaciers. Since the late 1950s, the USGS has maintained a long-term glacier mass-balance program at three North American glaciers. Similar measurements began at Sperry Glacier, MT in 2005. Since the late 1950s, the 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. The USGS has measured the mass balance on Gulkana Glacier since 1967 as part of a program to document long-term glacier and climate trends. What does this mean for the glacier? 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. 2.1 Mass Balance Observations. Alaska Table 1. USGS began biannual measurements of glacier mass balance and meteorology at Alaska's Wolverine and Gulkana glaciers in … Table 2: Reported mass balance values of the observation period 2017/18, 2018/19 as well as *preliminary values for 2019/20. 3.2.  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. For example, the balance year at Gulkana Glacier starts and ends in September of each year. Explaining mass balance and retreat dichotomies at Taku and Lemon Creek Glaciers, Alaska. 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. annual balance was -2.04 m. Gulkana Glacier (lat 63'15' N., 1,700-m mean equilibrium line altitude) had a winter balance of 1.05 m, approximately normal for this glacier; the final annual balance was -0.30 m. INTRODUCTION The purpose of the International Hydrological Decade (1965-74) is to increase the understanding and to promote 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. The trends of climate change indicate that glacier melt will continue to increase. We derive historic ELA sensitivities to climate forcing using data from the U.S. Geological Survey (USGS) Benchmark Glacier program. 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. Mass Balance Factsheet for the Gulkana Glacier, Alaska. 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. 2b, c) with the most notable episode occurring in the late 1970s. For each glacier, the mass balance is set at zero for the base year of 1965. change from digital date, west gulkana glacier, alaska l. sam thompson and stephen e. smith ..... 11 determination of 1957-1986 mass balance of west gulkana glacier, alaska, by comparison of topographic maps fred b. chambers ..... 19 two-year mass balance of west gulkana glacier, alaska Episodes of positive glacier-wide mass balance (greater than uncertainty) have modulated mass loss at Wolverine Glacier several times since the observations began (Fig. 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. 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. of the Gulkana Glacier (from USGS database) Balance Year Winter Balance Summer Balance Net Balance 1966 0.93 1.03 -0.1 These glaciers have the longest continuous mass-balance records in North America, with winter balance Bw, summer balance Bs, and annual balance … This figure shows the cumulative mass balance of the three U.S. Geological Survey “benchmark” glaciers since measurements began in the 1950s or 1960s. Using data for the last 10 years and the first 10 years of the dataset, calculate the average annual glacier-wide mass balance … 2016). 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. The net mass balance on Gulkana Glacier has been measured since 1966 by the glaciologi-cal method, in which seasonal balances are measured at three index sites and extrapolated over large areas of the glacier. Validation of Glacier Mass Balance Modeling Using USGS Measurements  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.