Our Polar Flight

Part VI — The Weather — By Jakob Bjerkens

The Weather

This part does not contain any scientific accounts of the meteorological observations undertaken by the expedition in King’s Bay, during the flight or during the twenty-four days’ stay in 87° 43′—this will be left for the scientific journals to publish. I shall only give here a characterization of the “polar-weather” as it was during 1925 and what was done in order to determine the best date for the start.

What kind of weather conditions must the flyers have for their journey towards the Pole?

First of all there must be no fog at the place where they have to land. Even if there is only a fog-belt extending a few meters above the ground, a landing is impossible and a “forced-landing” would almost certainly end in a catastrophe.

Further, the flyers must avoid passing through thick snow. The two flying-machines might easily lose sight of each other, and if, in order to keep in contact with each other, they should fly close together, there is always the danger of a collision.

An overcast sky without rainfall is also useless. At least it must clear now and again sufficiently to make it possible to navigate by the sun. It is of course known that steering by the magnetic compass is very uncertain so far north, as the extent of the deviations in the Arctic is not sufficiently known.

Luckily so much is known about the weather in the polar ice region that it is possible to choose in advance the most suitable time of year for a polar flight. First of all, Nansen’s expedition by the “Fram” in 1893–1896 has given us this knowledge about the polar weather. During almost the entire time of their drift across the Arctic observations were made nearly every two hours in the course of the day, so that a singularly rich stock of information exists. The observations have been thoroughly gone through by the late Professor H. Mohn, so that we have got them set out now in a most perspicuous form. Both the observers’ and Professor Mohn’s calculations are published in the work, “The Norwegian North Polar Expedition XVII Meteorology.”

I am going to cite some figures from this book which give a clear reply to the question, Which time of the year is the best for flying to the Pole?

In the three years which the drift lasted the approximate number of clear days per month were:

In January	14
„ February	12
„ March	9
„ April	8
„ May	7
„ June	0
„ July	0
„ August	0
„ September	0
„ October	4
„ November	11
„ December	15

Thus in midwinter (December and January) nearly half of each month is composed of clear days, but the number quickly declines towards the summer and there are none in the four months from June to September. It happens, of course, that in the summer time the sun breaks through the sky at some time of the day, but even that is not very often. June had on an average twenty-six overcast days, July twenty-seven, August twenty-four, and September twenty-seven days.

As might be expected, downpours are much more frequent in the gray summer months than in the other part of the year. The number of days with rainfall were, on an average, as follows:

In January	11
„ February	11
„ March	13
„ April	13
„ May	20
„ June	20
„ July	21
„ August	19
„ September	22
„ October	14
„ November	9
„ December	9

Therefore one can count that two-thirds of all the days from May to September have rain or snow-falls. In the winter time, on the other hand, only one-third of the days have downpours.

Fog—the flyer’s worst enemy—also collects during the summer half of the year. Foggy days on an average were:

In January	0
„ February	0
„ March	2
„ April	1
„ May	2
„ June	10
„ July	20
„ August	16
„ September	10
„ October	4
„ November	1
„ December	0

One is therefore pretty sure to be without fog until May, but from June to September it is general. First, in October the fog begins to get less and then disappears altogether in the middle of winter.

It appears quite clearly from the “Fram” observations that only the dark period of the year has somewhat stable weather conditions, with a clear sky. During the light period of the year the weather is gray and thick.

These conditions are as unfavorable as possible for all flying expeditions towards the Pole. The good weather during the winter—October to March—cannot be taken advantage of on account of the darkness, and it is necessary to be satisfied with the much more unfavorable weather during the lighter period of the year.

Luckily there is, however, an intermediate condition of weather, when the light is still there, but the summer’s gray weather has not yet set in properly. April with its eight clear weather days, seventeen days without downpours, and only one foggy day ought to offer the best conditions for flying. Only one has to remember that when flying over a longer distance the chances of getting into ugly weather are much greater than one would imagine from the impression given by the figures. In a distance of an extent equaling that from Spitzbergen to the Pole, during a good month such as April, one will in most cases have to pass through a bad and good weather-zone. In April, too, one has to reckon with severe cold. “Fram” had a temperature as low as -38° 4 c. in the month of April and even at the end of that month it can go down to -29° c. If it is, therefore, one’s intention to fly on a day of good weather, it is necessary to be well protected against the severe cold.

In 1925 the polar flight could not be undertaken as early as April. Notwithstanding the fact that the journey from Norway was undertaken before the real opening of the shipping season, and that the preparations in King’s Bay proceeded quickly and according to program, our machines were not ready to start until the beginning of May. An earlier start might well have been possible if the previous winter had been spent in Spitzbergen.

It was the business of the meteorologists to determine which was the best day in the month of May for the start. With “Fram’s” experiences before us the prospects of finding a good starting day were not very rosy. In May, 1896, when “Fram” was about halfway between Spitzbergen and the Pole, there were twenty-five days with rainfall, and only three days at the beginning of the month had clear weather. Should May, 1925, turn out just as bad as May, 1896, the polar flight would take place under very risky meteorological conditions.

What resources were now at our disposal to determine what kind of weather was expected? First were the telegrams from the stations in the neighborhood, indicating the kind of weather which was approaching. This system is commonly used by all meteorological institutions which have something to do with weather reports, and it was therefore only natural that this should be made use of for the polar flight. One can, however, know beforehand that to make weather forecasts at Spitzbergen is much more difficult than at other places where it has been tried before. For instance, Southern Europe is covered by a network of telegraph stations which can report the approaching weather. But in Spitzbergen it is not so easy. The network of European stations certainly give reports of every condition approaching from the south, but no telegraphic weather reports can be obtained from the west, north, or east. There are, therefore, many situations where the meteorologists, notwithstanding all the aid, can give no reply to the question: “What will the weather be like to-morrow?”

And that is the case in Spitzbergen. But the polar flight had to be undertaken from there, and had to extend more than 1,000 kilometers above unknown regions in unknown weather conditions! How could any one guarantee good weather for the whole distance?

I know that many meteorologists would reply to such a question that this is beyond science. To prophesy what the weather will be like near the Pole is pure guesswork. As now and again stress has been put upon this view in the press, may I be permitted to defend the foolhardiness I showed by venturing to tackle this problem? I admit that it is very often quite impossible to say what the weather will be like on the way from Spitzbergen to the Pole, and still less possible to predict how it is likely to turn out in a day or two’s time. But meteorology allows us to determine by indirect conclusions whether the prospects of good weather are bright or whether the situation is too risky. That these weather forecasts are based on very weak foundations, and therefore can easily turn out wrong, was known by the airmen from the first hour. Still they preferred to follow the advice science could give, even if it was often vaguely formulated and given with all sorts of provisos.

The plan was not to risk a flight in any case through fog and thick snow, where the aeroplanes would certainly lose sight of each other, but to turn back if the weather should begin to look too threatening. It would then be the meteorologists’ problem to find another occasion when it would be again worth while to try and see whether in a renewed attempt the way to the Pole would be clear.

For several years the exchange of meteorological weather reports had been broadcast by wireless so that everybody who had a receiving apparatus could make free use of the same. “Fram’s” receiving apparatus was of the latest type and worked very well, even receiving meteorological messages from countries very far distant. Mr. Devoid attended to the receiving of nearly all the weather reports—a job he was well acquainted with, through his position as assistant at the Geophysical Institute at Tromsö. It can safely be said that we could not have got a better man for the handling of all the radio weather news which came to hand. He was untiring in trying to pick up and read communications which were very weak, coming from far distant stations, and it was, thanks to him, that the weather forecasting station at King’s Bay was able to work with nearly the same full range of meteorological observations as any southern weather forecasting station.

The meteorological despatches are broadcast by international agreement and, with one single apparatus, one can receive accounts of observations from the whole of Europe, North America and North Asia. That has been made possible by the various countries all having come to an agreement, in which they have arranged to send despatches following each other closely according to a prearranged time-table. On the “Fram” we regularly received the following despatches: