Six main British Antarctic Survey stations were occupied throughout the year. Of these, Adelaide air base on Adelaide Island was closed down at the end of the summer, as it has been replaced by a new station, Rothera, 64 km to the north–east. A snow runway near the new site had been brought into useforthe 1975–76 summer by a party camping in the area, and a small hut built there later in the season was occupied by four men during the 1976 winter. In the 1976–77 summer a small hut and all moveable equipment and stores were transferred from Adelaide, and extensive new living quarters and a generator shed constructed with the help of summer visitors. There are now 13 men at the station, including several builders who are completingthe interior work. The original hut which provided temporary living accommodation for 15 men is now used as a store. A number of field stations were also occupied during the 1976–77 summer.

The Greenland Ice Sheet Program (GISP) in August 1975 completed its fourth successful field programme since its beginning in 1971. The GISP research is aimed at the investigation of glaciological, geophysical, geochemical and palaeo-climatological parameters of the Greenland ice sheet and at the interpretation of these factors in terms of climatic significance for the present and for the future.

Six British Antarctic Survey stations were operational during the year. A new station, at Rothera Point, Adelaide Island, is being built to replace Adelaide station. Its development is providing a unique opportunity to study changes in the microbial, invertebrate, plant and birdpopulations as a result of human activities, including the inevitable atmospheric pollution and the localized influence of tracked vehicles. Several small sites have been set up to study these changes. Among the senior Survey staff to visit the bases this season were Dr R. M. Laws (Director), and Mr W. R. Piggott (Head of Atmospheric Sciences). Other visitors included Dr B.B. Roberts, Dr L. Ferraz, a Brazilian observer, and Mr D. Smith, a British artist.

The Ross Ice Shelf is a floating sheet of ice about the size of France. It ranges in thickness from 200 m to approximately 1 000 m. The Ross Ice Shelf Project (RISP) seeks to shed more light on the ice shelf's relationship to the west Antarctic ice sheet and on the possibility that significant fluctuations in thickness and extent have taken place during recent history. The project also aims to learn more about the unique ecological system in the unexplored waters under the ice shelf and in the sediments which floor the Ross Sca embayment.

A joint geological expedition from the Department of Geology, University of Cambridge, and the Geologisch-Palontologisches Institut der Universitt Hamburg worked in Svalbard from 27 June to 12 September and was based at the building Mexico in Ny-lesund. The expedition totalled 17 members, was organized from Cambridge by Ailsa B. Reynolds, and was led by W. B. Harland.

Current theories and observations in magnetospheric physics suggest that low-energy particle fluxes, exhibiting the characteristics of solar-wind particles, have direct access to certain regions of the high-latitude polar ionosphere (Akasofu and Lanzerotti, 1975). The precipitation of these particles occurs over a few degrees of latitude and several hours of magnetic time (centred on geomagnetic noon) and this region has been termed the dayside magnetospheric cleft (Vasyliunas, 1974). The resultant phenomena, such as dayside auroral emissions, have not been extensively studied due to the rather remote location of accessible land mass at latitudes high enough for observations at local apparent noon to be made (Fig 1). Magnetospheric cleft observations have been carried out from instrumental aircraft (Whalen and Pike, 1973) and from Cape Parry, NWT (Peterson and Shepherd, 1974) in previous winters. Aircraft observations are, obviously, of limited duration and twilight at Cape Parry severely restricts photometric observations.

The Mrdalsjkull ice cap, in southern Iceland, was visited in July and August 1975 by a party of seven, operating from a base camp on its western side, at the head of the Prsmrk valley. The objectives of the expedition were to record evidence of changes in the extent of the ice cap since its last re-advance (about 1850?) with a view to correlation with climatic data, and to examine the role of imagery from the Earth Resources Technology Satellite-1 (ERTS-1) in this context.

The Ross's Gull breeds between 62°27' and 70°30'N and 142° to 160°E in wet alder and birch scrub in the deltas of some of the larger north flowing rivers of north-eastern Siberia (Buturlin, 1906; Dementiev and Gladkov, 1951). The species was first discovered on 23 June 1823 by James Clark Ross, then a lieutenant with W. E. Parry's second expedition in search of the North-west Passage. At the time, they were stationed at Igloolik, east Melville Peninsula, in the central Canadian Arctic (Stenhouse, 1930). Ross, once more in company with Parry, saw the species again north of Spitsbergen during their attempt at the pole in July 1827.

A seven-man party from the Polytechnic of Central London spent from 25 July to 26 August in north-west Spitsbergen. Field work included botanical survey and sampling, recording of human sleep patterns, and the making of a 16 mm colour film. The party had the support facility of a former Scottish fishing vessel, the Copious, which it shared with the Cambridge Spitsbergen Expedition. The group landed in the far north of Vasahalvøya on Makarovbreen. Overland glacier journeys were made from Makarovbreen south to Liefdef jorden and Bockf jorden, and from the lower end of Woodf jorden across to Kongsf jorden via Blomstrandbreen—roughly 160 km in all.

Roslin Gletscher is a sub-polar glacier in the central Stauning Alper which lie at 72°N in east Greenland. Interest has been focussed on this glacier in recent years since it is clearly of the surging type. The primary aim of the expedition was to survey a longitudinal profile of the glacier and to re-survey stake lines established by previous expeditions to measure ice flow rates. It is hoped that the results will throw some light on the stage of the surge cycle that has been reached. This should improve predictions of when the next surge may occur and allow closer study of the mechanisms which cause the glacier to surge. A secondary aim was to relocate a food and equipment dump, left from earlier expeditions, which was threatened by moraine movement.

This expedition to the Blosseville Kyst area of east Greenland was wholly geological, comprising several groups brought together under the leadership of Professor P. E. Brown of Aberdeen University. It aimed to follow up geological discoveries which had been made in 1971 by expeditions from Cambridge and Sheffield, and also to pursue several new lines of research directed primarily at relating the sediments and volcanic rocks in east Greenland to the birth of the North Atlantic Ocean. The expedition chartered mv Signalhorn from Martin Karlsen AS of Brandal, Norway, for a period of 52 days; after some delay, due to a mechanical emergency in the North Sea, she sailed from Aberdeen on 20 July. The journey was slow and rough and featured an abortive attempt to take the shorter route round north-east Iceland. On 26 July the east Greenland coast was sighted at lat 68 N in fine weather. Aputitq and the Kangerdlugssuaq area were beset by heavy pack ice, but good progress was made northwards along Blosseville Kyst through moderately open water about five miles offshore.