Milne Glacier, Northern Ellesmere Island, N.W.T., Canada: a Surging Glacier?

Abstract

ABSTR ACT . D urin g th e pe riod 1966 to 1983 Miln e Gl ac ier ad va nced 4 .25 km a t a mea n allnual rate of 250 m a -I , Sin ce s urges commonly occ ur over a two o r three yea r pe ri od th e maximum rate of ad van ce could have been g rea te r than 2 km a -I . Th e g lacier terminus has a number offea tures indi cat ive of past surge be h avio ur. O f these, a t leas t three looped mo ra incs sugges t surges of th e ma in va lley g lacier a nd tributa r y g laciers . As Miln e Gl acier is a cold g lac ier, surges may poss ibl y be Ih e rm a ll y reg ula led . A cc umul a tion ra tes on th e ice ca ps o f no rth ern Ell es mere Island are low h en ce a c riti ca l condition in th f' " rese rvoir a rea " will be o nl y slowly a tta ined. A s a consequence th e periodi city o f surges in \I1iln c Glac ier a nd othe r Hi g h Arc ti c g lac iers is ex pec ted to be hi gh. In a -I . Du fa it que les surges habituell em ent se pro cilli sent en 2 o u 3 a ns, la vitesse max imal e d 'avan tce peu t avail' c te supe ri e llre it 2 km a -' . Le fr o nt e1 u g laci er prcscnt c plusieurs ca racteri stiqu es n?\'ela tri ces d ' un co mpon emt"' nt d e surge d a ns le passe. Entre a lllres, a ll ma ins trois mo ra ines sinll clI s('s slIggc re nt des surges nu glac ie r d e va ll ee princ ipal ct d es amu e nts. Comlll e le g lac ie r Mi ln e es t un glac ier fro id , les surges pcuven t etre reg ul ees th en n iqueme nt. -Smith, 1964. Observations made in spring 1983 indicate that Milne Gl acier has advanced rapidly during the past 15-25 years . Evidence of surge behavior is presented in thi s paper . MILNE ICE SHELF AND MILNE GLACIER, 1959 TO 1983A Canadian National Topographic Survey map (340E & 340H) of Milne Ice Shelf and Milne Glac i er ( Fig. 1) was produced with the aid of air photographs taken in July 1959 (Fig. 2) . At that time the glacier front adjoined the ice shelf although ice wasting and disintegration had created two areas of l ake ice along the east and west shores (Fig . 1). The lower 13 km of Milne Glacier consists of three i ce streams . The east tongue is composed of ice from the main valley glac i er plus that of a tributary gl ac i er which flows int o the north side of the va lley 19 km from the ice front . Ice issuing from Gl ac i er 5 creates a west tongue . A number of features on the surface of Mi l ne Glacier are suggestive of past su rge behavior : 1) contorted mora in es, 2) moraine-covered stagnant ice at the terminus, and 3) irregular surface drainage , especially on the east slIr Ics ca lo ttcs d e g lace d e la parli e nord de rile d ' Ellesm e re sa nt faibl es, d e ce fa it la condition critique dans la "zone rese rvoir" se ra atte inte se ul emcnt lentement. En consequence la pe riodi cite d es surges sur le g la c ie r Mi ln c et sur d 'a utres g la c ie rs dl! haUL Arc tiquc es t supposee g rand e . ZUSAMM EN FA SSUN G . Milne Clacier im Nordern von Ellesmere i sland, N. W T. ,Karrada: eill ausbreclrender CIe/sclrer' Im Zeilra um von 1966 bis 1983 sliess d er Milnc Glac ie r um...

Area change of glaciers across Northern Ellesmere Island, Nunavut, between ~1999 and ~2015

“…The observed surge was from Otto Glacier (G82716W81419N), a glacier that was reported to have surged between 1950 and 1959 (by Hattersley-Smith, 1969) and continued to surge or surge again by 1999 (Copland and others, 2003). An active surge was also reported for the Milne Glacier from 1966 to 1983, when the glacier advanced by 4.25 km at a rate of 250 m a −1 (Jeffries, 1984). Based on the recent surge activity of the Otto and Milne Glaciers, it is possible that the losses reported in our study (22.54 and 19.48 km 2 , respectively) may be linked to the quiescent phase of their surge cycles.…”

Volume and area changes of the Milne Ice Shelf, Ellesmere Island, Nunavut, Canada, since 1950

“…Area loss at the rear of the ice shelf primarily resulted from deterioration of the Inner and Central Units as ice shelf ice (thicker ice with a ridged surface) transitioned to lake ice (thinner ice with a smooth surface) (Figure 6). Terminus advance of the surge‐type Milne Glacier [ Jeffries , 1984] by >5 km between 1950 and 2009 also contributed to Inner Unit area loss because glacier ice displaced the Inner Unit ice shelf ice [ Mortimer , 2011].…”

“…In 1959 it appears as though Milne Glacier's terminus had pushed the Inner Unit ice forward and compressed the ridges and troughs near the glacier's terminus [ Jeffries , 1984]. This may indicate that the Inner Unit consisted of thinner ice at this time (Figure 6b, yellow ellipse).…”

First Landsat multi-spectral scanner images of the Canadian Arctic north of 80°N

“…Milne Glacier, a trunk glacier flowing northward into Milne Fiord and the Milne Ice Shelf, has numerous medial moraines. The curvilinear nature of those moraines is believed to be evidence that the Milne Glacier or one of its tributaries is also a surge-type glacier (Jeffries 1986).…”

“…Chapman Glacier was identified as a surge-type glacier on the basis of contorted moraines and an irregular surface drainage pattern (Hattersley-Smith 1969). The curvilinear nature of those moraines is believed to be evidence that the Milne Glacier or one of its tributaries is also a surge-type glacier (Jeffries 1986). 4) and the Landsat image suggests there has been very little change at Chapman Glacier since 1959.…”