Of one thing we were certain, and that was that Adelie Land was the windiest place in the world. To state the fact more accurately: such wind-velocities as prevail at sea-level in Adelie Land are known in other parts of the world only at great elevations in the atmosphere. The average wind-velocity for our first year proved to be approximately fifty miles per hour. The bare figures convey more when they are compared with the following average annual wind-velocities quoted from a book of reference: Europe, 10.3 miles per hour; United States, 9.5 miles per hour; Southern Asia, 6.5 miles per hour; West Indies, 6.2 miles per hour.
Reference has already been made to the fact that often the high winds ceased abruptly for a short interval. Many times during 1913 we had opportunities of judging this phenomenon and, as an example, may be quoted September 6.
[TEXT ILLUSTRATION]
A diagrammatic sketch illustrating the meteorological conditions at the main base, noon, September 6, 1913
On that day a south-by-east hurricane fell off and the drift cleared suddenly from about the Hut at 11.20 A.M. On the hills to the south there was a dense grey wall of flying snow. Whirlies tracked about at intervals and overhead a fine cumulus cloud formed, revolving rapidly. Over the recently frozen sea there was an easterly breeze, while about the Hut itself there were light northerly airs. Later in the day the zone of southern wind and drift crept down and once more overwhelmed us. Evidently the "eye" of a cyclonic storm had passed over.
During September the sea was frozen over for more than two weeks, and the meteorological conditions varied from their normal phase. It appeared as if we were situated on the battlefield, so to speak, of opposing forces. The pacific influence of the "north" would hold sway for a few hours, a whole day, or even for a few days. Then the vast energies of the "south" would rise to bursting-point and a "through blizzard" would be the result.
On September 11, although there was a wind of seventy miles per hour, the sea-ice which had become very solid during a few days of low temperature was not dispersed. Next day we found it possible to walk in safety to the Mackellar Islets. On the way rushes of southerly wind accompanied by a misty drift followed behind us. Then a calm intervened, and the sun momentarily appeared and shone warmly. Suddenly from the north-west came breezy puffs which settled into a light wind as we went north. On the way home we could not see the mainland for clouds of drift, and, when approaching the mouth of the boat-harbour, these clouds were observed to roll down the lower slopes of the glacier and, reaching the shore, rise into the air in columns. They then sailed away northward at a higher altitude, almost obscuring the sun with a fine fog. On the same night the "south" had gained the mastery, and the wind blew with its accustomed strength.
Again, on September 24, McLean had a unique experience. He was digging ice in a fifty-mile wind with moderate drift close to the Hut and, on finishing his work, walked down to the harbour-ice to see if there were any birds about. He was suddenly surprised to leave the wind and drift behind and to walk out into an area of calm. The water lapped alongside the ice-foot, blue in the brilliant sunlight. Away to the west a few miles distant a fierce wind was blowing snow like fine spume over the brink of the cliffs. Towards the north-west one could plainly see the junction between calm water and foam-crested waves. To the south the drift drove off the hills, passed the Hut, and then gyrated upwards and thinned away seawards at an altitude of several hundred feet.
The wind average for September was 36.8 miles per hour, as against 53.7 for September of the previous year. There were nine "pleasant" days, that is, days on which it was possible to walk about outside and enjoy oneself. On the 27th there was a very severe blizzard. The wind was from the south-east: the first occasion on which it had blown from any direction but south-by-east at a high velocity. The drift was extremely dense, the roof of the Hut being invisible at a distance of six feet. Enormous ramps of snow formed in the vicinity, burying most of the cases and the air-tractor sledge completely. The anemograph screen was blown over and smashed beyond all repair. So said the Meteorological Notes in the October number of the 'Adelie Blizzard'.
Speaking of temperature in general, it was found that the mean-temperature for the first year was just above zero; a very low temperature for a station situated near the Circle. The continual flow of cold air from the elevated interior of the continent accounts for this. If Adelie Land were a region of calms or of northerly winds, the average temperature would be very much higher. On the other hand, the temperature at sea-level was never depressed below-28 degrees F., though with a high wind we found that uncomfortable enough, even in burberrys. During the spring sledging in 1912 the lowest temperature recorded was -35 degrees F. and it was hard to keep warm in sleeping-bags. The wind made all the difference to one's resistance.