Contribution of Arctic seabird-colony ammonia to atmospheric particles and cloud-albedo radiative effect

B Croft; G R Wentworth; R V Martin; W R Leaitch; J G Murphy; B N Murphy; J K Kodros; J P D Abbatt; J R Pierce

doi:10.1038/ncomms13444

Contribution of Arctic seabird-colony ammonia to atmospheric particles and cloud-albedo radiative effect

Nat Commun. 2016 Nov 15:7:13444. doi: 10.1038/ncomms13444.

Authors

B Croft¹, G R Wentworth², R V Martin^{1

3}, W R Leaitch⁴, J G Murphy², B N Murphy⁵, J K Kodros⁶, J P D Abbatt², J R Pierce^{1

6}

Affiliations

¹ Department of Physics and Atmospheric Science, Dalhousie University, 6310 Coburg Road, Halifax, Nova Scotia, Canada B3H 4R2.
² Department of Chemistry, University of Toronto, 80 St George Street, Toronto, Ontario, Canada M5S 3H6.
³ Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, Massachusetts 02138, USA.
⁴ Climate Research Division, Environment and Climate Change Canada, 4905 Dufferin Street, Toronto, Ontario, Canada M3H 5T4.
⁵ Department of Environmental Science and Analytical Chemistry (ACES) and Bolin Centre for Climate Research, Stockholm University, Svante Arrhenius väg 8, SE-11418 Stockholm, Sweden.
⁶ Department of Atmospheric Science, Colorado State University, 3915W. Laporte Avenue, Fort Collins, Colorado 80523, USA.

Abstract

The Arctic region is vulnerable to climate change and able to affect global climate. The summertime Arctic atmosphere is pristine and strongly influenced by natural regional emissions, which have poorly understood climate impacts related to atmospheric particles and clouds. Here we show that ammonia from seabird-colony guano is a key factor contributing to bursts of newly formed particles, which are observed every summer in the near-surface atmosphere at Alert, Nunavut, Canada. Our chemical-transport model simulations indicate that the pan-Arctic seabird-influenced particles can grow by sulfuric acid and organic vapour condensation to diameters sufficiently large to promote pan-Arctic cloud-droplet formation in the clean Arctic summertime. We calculate that the resultant cooling tendencies could be large (about -0.5 W m^-2 pan-Arctic-mean cooling), exceeding -1 W m^-2 near the largest seabird colonies due to the effects of seabird-influenced particles on cloud albedo. These coupled ecological-chemical processes may be susceptible to Arctic warming and industrialization.

Publication types

Research Support, Non-U.S. Gov't