Environmental Change in the Northern Ellesmere Region

Environmental Change in the Northern Ellesmere Region

IN THIS ISSUE BREAK-UP AND CLIMATE CHANGE AT CANADA’S NORTHERN COAST, QUTTINIRPAAQ NATIONAL PARK Warwick F. Vincent, Derek R. Mueller and Patrick Van Hove SPRING/SUMMER 2004 Break-up and Climate Change Different climate models vary in their pre- northern limit of North America, at the at Canada’s Northern Coast, diction of how fast the world is heating up in highest continental latitudes that are likely Quttinirpaaq National Park 1 different regions, but almost all converge on to experience the strongest impacts of global the conclusion that the north polar region change. Fat as an Ecological Tool: will experience greater temperature increas- Our work on Ellesmere Island first began Bears and Seals in Temperate es than elsewhere, and that these changes in the mid-1990s on Lake Hazen, the largest and Arctic Ecosystems 6 are likely to become ever faster because of waterbody in the park and one of the deep- the positive feedback effects of melting snow est lakes in the circumpolar Arctic. The New Look for the Canadian Polar and ice. This “runaway change” scenario frigid, clear waters of this lake were found to Commission Web Site 10 makes northern Canada a particularly im- be well-mixed to at least 100 m in summer, portant place for monitoring the global cli- in sharp contrast to lakes further to the Forty Years of Polar Research 11 mate system. Of course apart from our inter- south where a warm surface layer overlies national responsibilities in this regard, we colder water in summer. This deep summer The Involvement of Women in also have a vital self-interest in knowing mixing in Lake Hazen is likely to regulate its Self Government Negotiations 14 how fast the Canadian environment is ecology, but could eventually be dampened changing. and cease under warmer temperatures. His- Horizon 16 One of the remarkable features of Cana- torical studies in northern Finland, for ex- dian geography is that the landmass spans ample, have shown that the shift in lakes 41 degrees of latitude, with the northern tip from summer mixing to a layered structure of Ellesmere Island, Nunavut, extending to is accompanied by major changes in biolog- latitude 83°N, only a few hundred nautical ical species composition and in their aquatic miles from the North Pole (Fig. 1). This food webs. Lake Hazen is readily monitored northernmost coast includes Quttinirpaaq from space, and future changes in water (“Top of the World” in Inuktitut) National colour, temperature and duration of ice Park, a vast region containing the highest cover will provide indications of the pace of mountains in eastern North America, alpine environmental change. snowfields, glaciers, rivers, wetlands, strik- The northern coast of Ellesmere Island ing polar desert landscapes, lakes and deep was first explored by Europeans during the fiords. These environments and their biolog- British Arctic Expedition in 1875–76. Lieu- ical communities are shaped by extreme tenant Pelham Aldrich led a sledging party cold and are likely to be sensitive indicators from this expedition along the coastal fringe of climate. Furthermore, they are at the of undulating ice, and named many of the Northern Fig. 1 Ellesmere Fine Beam RADARSAT-1 image of the northern end Island of Quttinirpaaq National Park,Nunavut (September 27,2003). The main crack in the Ward Hunt Ice Shelf is traced in black,the southern edge of the ice shelf is traced in white. The dotted line marks the shoreline of Disraeli Fiord which continues for 20 km off the image. Note the ice breaking up in Disraeli Ford and in Lake A (unofficial name). Photo: © Canadian Space Agency/Agence spatiale canadienne 2003,received by the Canada Centre for Remote Sensing,and processed and distributed by RADARSAT International. 5 10 15 km 2 features that lie now within the northern boundary of Quttinirpaaq National Park. Ward Hunt Island, just off the northern coast of Ellesmere Island, was named after George Ward Hunt, First Lord of the Admiralty, while Disraeli Fiord was named after the Prime Minister of England at the time, Ben- jamin Disraeli. Even today, however, several important features of this remote region have yet to be named. For example, the 0 m remarkable set of deep, saline lakes along Ice cover (1–2 m) the northern coastline, only discovered a few decades ago, still bear the unofficial SPRING/SUMMER 2004 1999 2001 codes Lake A, Lake B and Lakes C1, C2 and C3. Aldrich had some unfavourable com- 5 m ments to make about the undulations in the coastal ice (“large and troublesome hum- mocks in the snow and ice”) and later the American explorer Robert Peary further sur- veyed this region and confirmed the difficul- 10 m ty of travel. Today these undulations can be made out clearly in the beautiful high reso- lution images produced by the Canadian 0 0.5 1 0 0.5 1 0 0 satellite RADARSAT (Fig. 1). We first visited Salinity ( /00) Salinity ( /00) this region in 1998 and discovered that these Fig. 2 undulations are formed by ridges between Salinity changes in the surface waters of Lake A between parallel, elongate meltwater lakes that con- Ellesmere Island at their southern ends. 1999 and 2001. The unusual ice-out event seen by tain rich communities of microscopic organ- From Peary’s detailed account of his voyage RADARSAT in late summer 2000 allowed the wind- isms. The latter occur in such abundance along the coast from Cape Sheridan to Axel induced mixing of deeper saline waters into the surface, and eliminated the surface freshwater habitat. Photo: that they produce conspicuous red coloured Heiberg Island, we estimated a total ice shelf 2 Warwick Vincent. “ice mats” that on closer inspection have extent of about 8900 km . This ice shelf is been found to contain viruses, bacteria, believed to have started to form about 4500 algae and even minute animals. These self- years ago and to be fully in place (surmised measurements decades earlier, suggesting contained, microscopic worlds are natural from the carbon 14 dating of driftwood that this lake rarely lost its ice cover. These laboratories that are helping us gain insight trapped on the landward side of the ice) capped lakes show the effects of hundreds if into how life survived, grew and evolved about 3000 years ago (Jeffries, 2002). Our not thousands of years of slow heating by during major freeze-up events on Earth in analyses suggest that there has been a 90% the solar radiation that penetrates through the past (Vincent et al., 2004). However, loss of this ancient feature over the course of the surface ice, gradually warming their -CANADIAN POLAR COMMISSION these ice-based ecosystems (“cryo-ecosys- the 20th century. mid-depth saline waters to surprising tem- tems”) appear to be dwindling rapidly. Several other components of the north- peratures. The absence of mixing means Using RADARSAT data from 1998 and ern Ellesmere Island environment provide that this heat is not returned to the surface 1999, we estimated the expanse of undulat- evidence of substantial change. The saline to be lost to the atmosphere, but rather can ing ice to be about 850 km2. This ice is sev- Lakes A-, B- and C-series are capped by slowly accumulate. Mean annual air tem- eral tens of metres thick, and forms a series thick ice through most months of the year, peratures in this region are around –20°C, of ice shelves that float on the sea and that and our initial profiling data from Lake A in yet Lake A reaches a stable 8.5°C in its mid- rise fall with the tides, while attached to 1999 bore a close resemblance to earlier depth, and Lake C1 attains an astonishing 3 12°C that is likely to stay fairly constant Disraeli Fiord. When we first undertook When we flew over the ice shelf in 2001 throughout the year despite winter air tem- measurements in this deep, 30 km-long we noted a central fissure, but were un- peratures below –40°C. In 2001 we ob- fiord we found that it contained a thick sur- aware of its extent or significance. In 2002, served for the first time that this unusual face layer of freshwater sandwiched be- we returned to the site and immediately saw layered structure of cold freshwater on tween a 2.5 m ice-cap above and the sea that the fissure was huge, had widened into warmer salt water was being broken down, beneath. The plankton was composed of an a crack that extended 15 km over the full and that there was evidence of mixing (Fig. unusual mixture of fresh and brackish water north-south length of the shelf, and was 2). RADARSAT images confirmed the loss of species (Van Hove et al., 2001), and provid- accompanied by multiple east-west fissures lake ice on all the lakes in the year 2000, ed another fascinating model system for extending off for many km. Working with and in late summer 2003, Lake A again understanding life processes in the polar our collaborator Martin Jeffries and the Uni- showed substantial break-up of its surface environment. This so-called “epishelf lake” versity of Alaska Fairbanks SAR Facility, we ice (Fig. 1). This abrupt change in tempera- was formed because the Ward Hunt Ice Shelf were able to obtain high resolution RADAR- ture and salinity is likely to completely alter acted as a dam across the mouth of Disraeli SAT images and to confirm that the ice shelf the structure and ecology of these unique Fiord (Fig. 1) and allowed the outflow of was in the process of disintegrating (Fig.

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