A framework model for current land condition in Iceland.

Iceland border the Arctic with cold maritime climate and a large proportion of the land placed at highland plateaus. About 1100 years of human disturbance, such as grazing and wood harvesting, has left much of the island's ecosystems in a poor state, ranging from barren deserts to areas with altered vegetative composition and degraded soils. We constructed a novel resilience-based model (RBC-model) for current land condition in Iceland to test which and how factors, including elevation, slope characteristics, drainage, and proximity to volcanic activity, influence the resilience and stability of ecosystems to human disturbances.

Iceland is an episodic source of atmospheric ice-nucleating particles relevant for mixed-phase clouds.

Ice-nucleating particles (INPs) have the potential to remove much of the liquid water in climatically important mid- to high-latitude shallow supercooled clouds, markedly reducing their albedo. The INP sources at these latitudes are very poorly defined, but it is known that there are substantial dust sources across the high latitudes, such as Iceland. Here, we show that Icelandic dust emissions are sporadically an important source of INPs at mid to high latitudes by combining ice-nucleating active site density measurements of aircraft-collected Icelandic dust samples with a global aerosol model.

Long-term dust aerosol production from natural sources in Iceland.

Unlabelled: Iceland is a volcanic island in the North Atlantic Ocean with maritime climate. In spite of moist climate, large areas are with limited vegetation cover where >40% of Iceland is classified with considerable to very severe erosion and 21% of Iceland is volcanic sandy deserts. Not only do natural emissions from these sources influenced by strong winds affect regional air quality in Iceland ("Reykjavik haze"), but dust particles are transported over the Atlantic ocean and Arctic Ocean >1000 km at times.

Ecosystem recharge by volcanic dust drives broad-scale variation in bird abundance.

Across the globe, deserts and volcanic eruptions produce large volumes of atmospheric dust, and the amount of dust is predicted to increase with global warming. The effects of long-distance airborne dust inputs on ecosystem productivity are potentially far-reaching but have primarily been measured in soil and plants. Airborne dust could also drive distribution and abundance at higher trophic levels, but opportunities to explore these relationships are rare.