Although it is inanimate, ice can produce a variety of subtle sounds, some loud, some barely discernible. It is very challenging to record these sounds because of several reasons. For example, the microphones are not intended to be outside in freezing temperatures for long periods of time and there is no way to protect them from the cold. Ice can make many different levels of sounds; some are loud, others are extremely quiet which means that it is problematic to make good quality recordings. The siting of the microphones is also crucial. In fact it is very rare to hear the sounds of the ice; the conditions have to be just correct in order that these sounds can be created and these optimal conditions do not occur every year.
The soundtracks on this publication have all been recorded by the lakeside or in woodlands near to the shoreline. Track nine is an exception, it was recorded on the ice itself about 30 metres from the shore. It is believed that this present publication is the very first recording made anywhere in the world of the sounds created by natural ice.
The publication of this recording was made possible by a grant from the Friends of Kuopio Nature (Kuopion Luonnon Ystäväin Yhdistys ry). In addition, I would like to acknowledge all of the people who have helped or contributed to the creation of this work. I express my special thanks to my wife, Maarit. She has listened patiently to all of these soundtracks and given valuable feedback at the various stages of the production. I dedicate this recording to all the individuals who have published sound material or soundscapes from the natural world (on either vinyl or CD) – your efforts have opened new perspectives for me and encouraged me to overcome the problems encountered.
Kuopio 9.7.2015
Lauri Hallikainen
Producer / Recording engineer
Introduction
The sounds of ice originate when it is very cold and the ice starts to contract so that cracks and crevices appear on its surface. The thinner the ice, the higher will be the sound, thick ice makes a much deeper sound. The depth of snow cover also influences the audibility and tones of the ice sounds. Changes in the atmospheric pressure also exert an effect since the ice responds to these changes by cracking and it this phenomenon which produces the sound.
The wind can hasten the formation of ice. This happens when the wind starts to blow from the north and the icy Arctic blasts displace warmer air. This kind of northerly wind can start the process of ice formation which is accompanied by a characteristic crackling sound (track 8).
Ice starts to form when the water temperature falls to 0°C. The salinity of the water influences its freezing temperature. All of the tracks on this recording originate from salt-free lake water. Ice will not form if some parts of the water are warmer than others, it is essential that there is a wide expanse of water at about five degrees with no fluctuations in temperature.
Track descriptions and background species
01 A snow-free expanse of ice on Lake Kallavesi in April (09'38'') The huge expanse of ice slumbers under the light of the stars. The crisp night frost has created a calm which looms over the woods, shore and the ice-covered lake. As the temperature drops during the early night, the ice field starts to come alive. Cracks and crevices start to appear in different parts of the ice field and their birth is accompanied by ice sounds. Tonight the ice creates its own barrage of sound which is not dampened by any snow cover. 8.4.2014 at 3.00 am, Kuopio, Kaislastenlahti. Ice thickness - variable, about 30 cm. Depth of snow on the ice 0 cm. Temperature at the time of recording about -16°C. Wind speed from the north-east 2 m/s.
02 Spring - and a babbling stream adds an accompaniment to the groans of the birth of crevices in the ice (12'00'') A small meandering stream emerges from the depths of the conifers to empty its contents into a grassy bay of the lake. Next to the fir trees by the shoreline, there is a small patch of glistening clear melt water. Beyond this small dark pool, lies a huge expanse of ice which extends as far as can be seen in the gloom of this spring night. Broken and arched water-reeds stretch out at the edge of the ice. In the quiet of this early morning, the burbling stream adds an accompaniment to the whines and groans as the ice breaks to form cracks and crevices. 16.3.2014 at 1.39 am, Kuopio, Kaislastenlahti. Ice thickness, about 40 cm. Depth of snow on the ice 1 cm. Temperature at the time of recording about -20°C. Wind speed from the north 2 m/s.
03 A spring night by the lakeside as the temperature plummets (09'12'') There is just a trace of purple in the western sky as a memory of the setting sun. The deep frost has cast a still, translucent blanket over the landscape. This evening, the stars are twinkling against the darkness of the heavens. The branches of the willow trees by the shoreline already are full of catkins. The intensity of the extreme cold causes the thick surface of the ice to begin to crack. 4.4.2014 at 8.52 pm, Kuopio, Hirvilahti. Ice thickness, about 35 cm. Depth of snow on the ice 0 cm. Temperature at the time of recording about -19°C. Wind speed from the north-west 1 m/s.
04 Early morning by the wooded shore as the autumn ice thickens (05'29'') The ancient birch trees which grow to the edge of the curved shoreline are covered in hoar-frost. Further up the bank, the tops of the tall pine trees stretch out towards the heavens. The wind has changed and now blows from the north-east and it has brought the first blasts of real winter to this northern spot. The plunging temperature triggers crackling sounds from the trees and moaning of the ice. 14.12.2009 at 3.15 am, Kuopio, Kaislastenlahti. Ice thickness - variable, about 1-5 cm. Depth of snow on the ice - variable, 0–5 cm. Temperature at the time of recording about -25°C. Wind speed from the north-east 1 m/s.
05 A south wind and the tinkling of the melting ice (07'18'') In the April twilight, the drifting ice flows still cover most of the lake. During the day, the wind changed and started to blow strongly from the south and this has caused the ice to move around. The conifer forest in the shadow of the lakeshore is still blanketed with snow but at the base of the tree trunks there are already snow-free bare patches. The gentle ebbs and flows of the spring wind resonate with deep tones through the wood stirring the shards of ice by the lakeside to create a tinkling sound. 17.4.2014 at 9.05 pm, Kuopio, Hirvilahti. Ice thickness – ice break-up, thickness of the ice flows about 35 cm. Depth of snow on the ice, 0 cm. Temperature at the time of recording +8°C. Wind speed from the south 5 m/s.
06 Beside a melted pool on a spring night by the lakeside (12'12'') The warm days of a sunny spring have melted a stretch of water along the shoreline. The waterfowl which have migrated to this lake are diving into the melted water by the edge of the ice. In some places, the snow-free ice resounds under the strain of the sub-zero temperature. 9.4.2014 at 2.37 am, Kuopio, Kaislastenlahti. Ice thickness- variable, about 30 cm. Depth of snow on the ice 0 cm. Temperature at the time of recording -18°C. Wind speed from the north-east 2 m/s. In the background of this recording you can also hear the Great Bittern and the Mallard.
07 Sounds like thunder emerge from beneath the snow cover of the ice (08'08'') The winter landscape is bathed by the light of a star-filled heaven. The arched branches of the snow-covered birch trees by the lakeside are pressing against each other. The plunging night-time temperatures have triggered the ice fields to make a rumbling sound which fills the stillness of the night. As morning approaches, the silence of the snowfields is broken by the repetitive cracks and groans of the ice coming from near and far. 8.3.2012 at 1.50 am, Kuopio, Hirvilahti. Ice thickness, about 40 cm. Depth of snow on the ice about 30 cm. Temperature at the time of recording about -18°C. Wind speed from the north 1 m/s. On this recording, in the background you can also hear the cry of the Eurasian Eagle Owl.
08 A north wind and the crackling of the freezing lake (7'00'') It is early morning at the end of October by the bank of a small lake. During the night, the wind changed and now blows from the north scuttling clouds across the star-filled heavens. The wind whispers and sighs through the branches of the fir and leafless birch trees by the shoreline. Stalks of the long grass on the beach are bent like arches by the weight of the frozen water droplets. 28.10.2012 at 6.05 am, Kuopio, Hirvilahti. Ice thickness – variable, about 0.5 cm. Depth of snow on the ice 0 cm. Temperature -4°C. Wind speed from the north 4 m/s.
09 A starry sky and the song of the ice in mid-December (8'25'') The recently fallen snow has formed a protective blanket over the ice by a sheltered bay but further away, the deeper parts of the lake are dark and snow-free. Under bright starry skies, the trees by the lakeside are shrouded by a delicate veil of snow. The ice on the lake resounds to create Mother Nature’s own symphony. This is the way that the northern wilderness gets itself ready to celebrate the imminent Christmas festival. 14.12.2009 at 4.30 am, Kuopio, Kaislastenlahti. Ice thickness - variable, about 1-5 cm. Depth of snow on the ice – variable, 0-5 cm. Temperature at the time of recording about -25 °C. Wind speed from the north-east 1 m/s.
Translated by Airi MacDonald and Ewen MacDonald 2015