Questions for Andrew Davidson

Marine biologist Andrew Davidson has observed changes in the proliferation and location of single celled organisms (phytoplankton) in Antarctic waters over recent years.

Read Andrew’s Comment below:

.

CategoriesUncategorized

One Reply to “Questions for Andrew Davidson”

  1. 1. What was your role in Antarctica and when did you work there?
    .

    I study the single celled organisms that inhabit the Southern Ocean, namely bacteria, viruses, phytoplankton (plants), and protozoa (animals). My first trip to Antarctica was in 1983 as part of my BSc Hons research and my most recent was in the 2006/07 as part of a marine science voyage. In total I have been to Antarctica and/or the Southern Ocean 14 times.

    What changes have you observed in the landscape as a scientist?
    Can you describe and/or explain them?
    .

    In the natural landscape, the most profound changes have occurred on the on Heard Island. This island is sensitive to warming global temperature as they exist at temperatures at the cusp between water existing as solid and liquid. Thus it is a canary in the cage for global climate change. Only a small temperature increase has seen major changes in ice cover. It is truly a gem in the Antarctic crown. It is virtually the only subantarctic island that has not suffered from the introduction of exotic pests (rats, mice, rabbits, goats, sheep etc). The volcanic nature of the island means its colours range from from jet black rocks and beaches to russet browns from iron rich minerals. Its shores are inhabited by a wealth of wildlife that comes there to breed over summer (e.g. chin-strap penguins and elephant seals). Once its glaciers proceeded from the peak of Big Ben (the central cone of the island) down its steep flanks almost to the shore. These glaciers have retreated markedly, exposing more of the inhospitable landscape that is reminicent of a moon-scape.
    Some of the most profound changes are associated with life on the Antarctic stations themselves. Gone are the rustic lines of shabby, wind blasted, leaky, but in their own way charming and delightfully ad hoc, accommodation and laboratories. With their passing was also lost a certain sense of adventure, tradition and living on the edge. In their are stead is positioned “leggo blocks” that enclose different functions of different colours – red, green, blue and yellow containing workshops, living quaters, powerhouse, and science respectively. These blocks are all connected by site services (water, power, ethernet cables etc) as though connected by an umbilicus to the source of all life, the thing that, perhaps above all else, allows us to inhabit the environment – electrical energy. While these leggo-land buildings provide a vast imporvement in the quality of life they have a soleless, characterless nature.

    Can you describe any changes you observed in the abstract qualities of the landscape, for example the changing colours between summer and winter, the changing length of dawn at different times of the year, the changing sound the wind at different times of day?
    .

    In the harsh light of day the Antarctic landscape is like looking at a photographic negative; starkly juxtaposed light from ice and snow against the old, dark, rocks. The rocks have been polished by glaciers, carved and riddled with hole by wind and ice and shattered by freezing of water in the cracks and fissures of the rock. But the rocks are unsullied by earth, growth of plants and their breakdown by oxidation at low temperatures is slow. Close inspection of the rocks reveals the delecate mineral structures and garnets and feldspars twingle in the starck light – almost in sympathy with the reflectance from ice crystals in the snow, ice faces from glaciers and the polished surfaces of wind scowers and the wind-polished surfaces of ice in fjords and on lakes.
    But Antarctica has gentler hues. There are the deep azure blues from fissures in ice bergs and lakes that form on the ice plateau. There are also the gentle rose-blossom hues of pink orange and red that bathe the landscape in the evenings that go on for ever as the sun skipps along the horizon but never disappears. These create a pinky relief of any projection from the ice surface, be it small snow mounds pressure ridges on the sea ice, sastrugi on the plateau and ice bergs ranging from old, melting and bizzarely sculpted bergs some of which look like battered viking longships through a vast spectrum of shapes and sizes to majestic tabular ice bergs that are 10’s and sometimes 100’s of km long. In addition, the evening skies often get a copper hue that creates a dramatic backdrop to the gentle pinks and steely, cold, blues and greys of ice formations.
    .
    And there are the winds, which have annoying characteristics like crossing you legs one over the other as you try and walk, of blowing the tea out of your cup, and sand blast your exposed flesh with dust, grit and ice shards. The wind that makes your donga (sleeping quaters before the advent of the new swish Living Quarters) vibrate and the guy-wires that hold it to the ground hum. The wind that mostly redistributes snow around the continent (there’s very little new precipitation in Antarctica), the scudding showers of which makes the hills seem dark menacing and indistinct, that blows wisps of spin-drift off the crowns of great ice bergs like thoughts and memories never to be recaptured. The wind that fashions the landscape, carving, scowering, and drilling its way into every surface and blows tiny shards of ice and snow through even the smallest crevice to settle as drifts. that shapes snow mounds and blizz-tails into aerodynamic shapes. The wind that turns the ocean into a maelstrom of seething walls of water exceeding 25 m in height with foaming crests that rush past like panicked stallions that toss you with slight of hand like a cork in a bottle. When in bed this variously stands you on your head, stands you unright, scrubs you across the sheets, then leaves you hanging almost weightless as the vessel falls from the crest of the wave only to bury itself at the bottom of the trough and stagger back up again, the entire vessel shaking and ringing like a gong struck by a heavy hammer.

    Is there any data (visual, numerical, visual, or written) that you have composed that I could work with to visually represent the changes?
    .

    Perhaps the sort of thing that may be useful as a source of visual material fro my scientific discipline would be remotely sensed images of ice distribution, sea surface chlorophyll and/or temperature changes in the distribution of organism with warmer water species progrssing southward, changes in the acidity of seawater and resulting changes in the solubility of calcium carbonate which some Antarctic organisms use to form their shells. As an example I’ll email you a version of the latter as a PowerPoint slide. See what you think and get back to me if this is the style of thing you’re after.

    Do you have any other comments you would like to make?
    .

    I hope that the above is what you are after. I am a little unsure what nature of changes you seek, so I tended to prattle on a bit and would perhaps benefit from a more rigid remit. Get back to me if you want me to ficus on specific aspects

Leave a Reply

Posted on Tuesday, July 31st, 2007