The Icelandic volcanic aeolian environment Processes and impacts — A review

Iceland has the largest area of volcaniclastic sandy desert on Earth or 22,000 km2
. The sand has been
mostly produced by glacio-fluvial processes, leaving behind fine-grained unstable sediments which are
later re-distributed by repeated aeolian events. Volcanic eruptions add to this pool of unstable sediments,
often from subglacial eruptions. Icelandic desert surfaces are divided into sand fields, sandy lavas and
sandy lag gravel, each with separate aeolian surface characteristics such as threshold velocities. Storms
are frequent due to Iceland’s location on the North Atlantic Storm track. Dry winds occur on the leeward
sides of mountains and glaciers, in spite of the high moisture content of the Atlantic cyclones. Surface
winds often move hundreds to more than 1000 kg m1 per annum, and more than 10,000 kg m1 have
been measured in a single storm. Desertification occurs when aeolian processes push sand fronts and
have thus destroyed many previously fully vegetated ecosystems since the time of the settlement of
Iceland in the late ninth century. There are about 135 dust events per annum, ranging from minor storms
to >300,000 t of dust emitted in single storms. Dust production is on the order of 30–40 million tons
annually, some traveling over 1000 km and deposited on land and sea. Dust deposited on deserts tends
to be re-suspended during subsequent storms. High PM10 concentrations occur during major dust storms.
They are more frequent in the wake of volcanic eruptions, such as after the Eyjafjallajökull 2010 eruption.
Airborne dust affects human health, with negative effects enhanced by the tubular morphology of the
grains, and the basaltic composition with its high metal content. Dust deposition on snow and glaciers
intensifies melting. Moreover, the dust production probably also influences atmospheric conditions
and parameters that affect climate change.
2016 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND