Interactions between the atmosphere, cryosphere and ecosystems at northern high latitudes

Michael Boy; Erik S. Thomson; Juan-C. Acosta Navarro; Olafur Amalds; Ekaterina Batchvarova; Jaana K. Bäck; Frank Berninger; Merete Bilde; Pavla Dagsson Waldhuserova; Dimistri Castaréde; Maryam Dalirian; Gerrit de Leeuw; Monika Wittman; Ella-Maria Duplissy (nèe Kyrö); J. Duplissy; A. M. L. Ekman; Keyan Fang; Jean-Charlet Gallet; Marianne Glasius; Sven-Erik Gryning; Henrik Grythe; Hans-Christen Hansson; Margareta Hansson; Elisabeth Isaksson; Trond Iverson; Ingibjörg Jónsdottir; Ville Kasurinen; Alf Kirkevåg; Atte Korhola; Radovan Krejci; Jon Egill Kristjansson; Hanna K. Lappalainen; Antti Lauri; Matti Leppäranta; Heikki Livhvainen: Risto Makkonon; Andreas Massling; Outi Meinander; E Douglas Nilsson; Haraldur Ólofsson; Jan B. C. Pettersson; Nonne L. Prisle; Ilona Riipinen; Pontus Roldin; Meri Ruppel; Matt Edward Salter; Maria Sand; Ovind Seland; Heikki Seppä; Henrik Skov; Joanna Soares; Andreas Stohl; Johan Ström; Jonas Svensson; Erik Swietlicki; Ksenia Tabakova; Thorstur Torsteinsson; Aki Virkula; Gesa A. Weyhenmeyer; Yusheng Wu; Paul Zieger; Markku Kulmala
2019 | Atmos. Chem. Phys. | 19 (2015-2061)

The Nordic Centre of Excellence CRAICC (Cryosphere–Atmosphere Interactions in a Changing Arctic Climate), funded by NordForsk in the years 2011–2016, is the largest joint Nordic research and innovation initiative to date, aiming to strengthen research and innovation regarding climate change issues in the Nordic region. CRAICC gathered more than 100 scientists from all Nordic countries in a virtual centre with the objectives of identifying and quantifying the major processes controlling Arctic warming and related feedback mechanisms, outlining strategies to mitigate Arctic warming, and developing Nordic Earth system modelling with a focus on short-lived climate forcers (SLCFs), including natural and anthropogenic aerosols.

The outcome of CRAICC is reflected in more than 150 peer-reviewed scientific publications, most of which are in the CRAICC special issue of the journal Atmospheric Chemistry and Physics. This paper presents an overview of the main scientific topics investigated in the centre and provides the reader with a state-of-the-art comprehensive summary of what has been achieved in CRAICC with links to the particular publications for further detail. Faced with a vast amount of scientific discovery, we do not claim to completely summarize the results from CRAICC within this paper, but rather concentrate here on the main results which are related to feedback loops in climate change–cryosphere interactions that affect Arctic amplification.

Arctic sea ice melt leads to atmospheric new particle formation.

Dall'Osto, M.; Beddows, DCS.; Tunved, P.; Krejci, R.; Strom, J.; Hansson, HC.; Yoon, YJ.; Park, KT.; Becagli, S.; Udisti, R.; Onasch, T.; O'Dowd, CD.; Simo, R.; Harrison, RM.
2017 | Sci Rep | 10

Future Response of Temperature and Precipitation to Reduced Aerosol Emissions as Compared with Increased Greenhouse Gas Concentrations

Navarro, JCA; Ekman, AML; Pausata, FSR; Lewinschal, A; Varma, V; Seland, O; Gauss, M; Iversen, T; Kirkevag, A; Riipinen, I; Hansson, HC
2017 | J Clim | 30 (3) (939-954)
air quality , circulation , climate response , earth system model , global climate , intertropical convergence zone , late 20th-century , noresm1-m , pollutants , sensitivity

Experiments with a climate model (NorESM1) were performed to isolate the effects of aerosol particles and greenhouse gases on surface temperature and precipitation in simulations of future climate. The simulations show that by 2025-49 a reduction of aerosol emissions from fossil fuels following a maximum technically feasible reduction (MFR) scenario could lead to a global and Arctic warming of 0.26 and 0.84 K, respectively, as compared with a simulation with fixed aerosol emissions at the level of 2005. If fossil fuel emissions of aerosols follow a current legislation emissions (CLE) scenario, the NorESM1 model simulations yield a nonsignificant change in global and Arctic average surface temperature as compared with aerosol emissions fixed at year 2005. The corresponding greenhouse gas effect following the representative concentration pathway 4.5 (RCP4.5) emission scenario leads to a global and Arctic warming of 0.35 and 0.94 K, respectively. The model yields a marked annual average northward shift in the intertropical convergence zone with decreasing aerosol emissions and subsequent warming of the Northern Hemisphere. The shift is most pronounced in the MFR scenario but also visible in the CLE scenario. The modeled temperature response to a change in greenhouse gas concentrations is relatively symmetric between the hemispheres, and there is no marked shift in the annual average position of the intertropical convergence zone. The strong reduction in aerosol emissions in the MFR scenario also leads to a net southward cross-hemispheric energy transport anomaly both in the atmosphere and ocean, and enhanced monsoon circulation in Southeast Asia and East Asia causing an increase in precipitation over a large part of this region.

Amplification of Arctic warming by past air pollution reductions in Europe

Acosta Navarro, J.; Varma, V.; Riipinen, I.; Seland, Ø.; Kirkevåg, A.; Struthers, H.; Iversen, T.; Hansson, H.-C.; Ekman, A. M. L.
2016 | Nat. Geosci. | 9 (277-281)

Multi-seasonal ultrafine aerosol particle number concentration measurements at the Gruvebadet observatory, Ny-lesund, Svalbard Islands

Lupi, A; Busetto, M; Becagli, S; Giardi, F; Lanconelli, C; Mazzola, M; Udisti, R; Hansson, HC; Henning, T; Petkov, B; Strom, J; Krejci, R; Tunved, P; Viola, AP; Vitale, V
2016 | Rend. Lincei.-Sci. Fis. Nat. | 27 (59-71)
aerosol size distribution , alesund , arctic aerosol , arctic air-pollution , arctic haze , boundary layer , cycle , lognormal fitting procedure , size distributions , summer , ultrafine aerosol concentration , winter , zeppelin station
The object of this study was to investigate the different modal behavior of ultrafine aerosol particles collected at the Gruvebadet observatory located in Ny-lesund (Svalbard Islands, 78A degrees 55'N, 11A degrees 56'E). Aerosol particle size distribution was measured in the size range from 10 to 470 nm typically from the beginning of spring to the beginning of fall during four (non-consecutive) years (2010, 2011, 2013 and 2014). The median concentration for the whole period taken into account was 214 particles cm(-3), oscillating between the median maximum in July with a concentration of 257 particles cm(-3) and a median minimum in April with 197 particles cm(-3). The median total number concentration did not present a well-defined seasonal behavior, as shown by contrast looking at the sub/modal number concentration, where distinct trends appeared in the predominant accumulation concentration recorded during April/May and the preponderant concentration of Aitken particles during the summer months. Lastly, the short side-by-side spring 2013 campaign performed at the Zeppelin observatory with a differential mobility particle sizer was characterized by an aerosol concentration mean steady difference between the two instruments of around 14 %, thereby supporting the reliability of the device located at Gruvebadet.

CO2-induced terrestrial climate feedback mechanism: From carbon sink to aerosol source and back

Kulmala, M.; Nieminen, T.; Nikandrova, A.; Lehtipalo, K.; Manninen, H.E.; Kajos, M.A.; Kolari, P.; Lauri, A.; Petäjä, T.; Krejci, R.; Hansson, H.-C.; Swietlicki, E.; Lindroth, A.; Christensen, T.R.; Arneth, A.; Hari, P.; Bäck, J.; Vesala, T.; Kerminen V.-M.
2014 | Boreal Environ. Res. | 19 (122-131)

Feedbacks mechanisms are essential components of our climate system, as they either increase or decrease changes in climate-related quantities in the presence of external forcings. In this work, we provide the first quantitative estimate regarding the terrestrial climate feedback loop connecting the increasing atmospheric carbon dioxide concentration, changes in gross primary production (GPP) associated with the carbon uptake, organic aerosol formation in the atmosphere, and transfer of both diffuse and global radiation. Our approach was to combine process-level understanding with comprehensive, long-term field measurement data set collected from a boreal forest site in southern Finland. Our best estimate of the gain in GPP resulting from the feedback is 1.3 (range 1.02-1.5), which is larger than the gains of the few atmospheric chemistry-climate feedbacks estimated using large-scale models. Our analysis demonstrates the power of using comprehensive field measurements in investigating the complicated couplings between the biosphere and atmosphere on one hand, and the need for complementary approaches relying on the combination of field data, satellite observations model simulations on the other hand.

Black carbon – Possibilities to reduce emissions and potential effects.

Hansson, HC.; Johansson, C.; Nyquist, G.; Kindbom, K.; Åström, S.; Moldanovna, J.
2011 | Report, ITM, SU | Report No: ITM report 202

Primary versus secondary contributions to particle number concentrations in the European boundary layer

Reddington, CL; Carslaw, KS; Spracklen, DV; Frontoso, MG; Collins, L; Merikanto, J; Minikin, A; Hamburger, T; Coe, H; Kulmala, M; Aalto, P; Flentje, H; Plass-Duelmer, C; Birmili, W; Wiedensohler, A; Wehner, B; Tuch, T; Sonntag, A; O'Dowd, CD; Jennings, SG; Dupuy, R; Baltensperger, U; Weingartner, E; Hansson, HC; Tunved, P; Laj, P; Sellegri, K; Boulon, J; Putaud, JP; Gruening, C; Swietlicki, E; Roldin, P; Henzing, JS; Moerman, M; Mihalopoulos, N; Kouvarakis, G; Zdimal, V; Zikova, N; Marinoni, A; Bonasoni, P; Duchi, R
2011 | Atmos. Chem. Phys. | 11 (23) (12007-12036)

General overview: European Integrated project on Aerosol Cloud Climate and Air Quality interactions (EUCAARI) – integrating aerosol research from nano to global scales

Kulmala, M; Asmi, A; Lappalainen, HK; Baltensperger, U; Brenguier, JL; Facchini, MC; Hansson, HC; Hov, O; O'Dowd, CD; Poschl, U; Wiedensohler, A; Boers, R; Boucher, O; de Leeuw, G; van der Gon, HACD; Feichter, J; Krejci, R; Laj, P; Lihavainen, H; Lohmann, U; McFiggans, G; Mentel, T; Pilinis, C; Riipinen, I; Schulz, M; Stohl, A; Swietlicki, E; Vignati, E; Alves, C; Amann, M; Ammann, M; Arabas, S; Artaxo, P; Baars, H; Beddows, DCS; Bergstrom, R; Beukes, JP; Bilde, M; Burkhart, JF; Canonaco, F; Clegg, SL; Coe, H; Crumeyrolle, S; D'Anna, B; Decesari, S; Gilardoni, S; Fischer, M; Fjaeraa, AM; Fountoukis, C; George, C; Gomes, L; Halloran, P; Hamburger, T; Harrison, RM; Herrmann, H; Hoffmann, T; Hoose, C; Hu, M; Hyvarinen, A; Horrak, U; Iinuma, Y; Iversen, T; Josipovic, M; Kanakidou, M; Kiendler-Scharr, A; Kirkevag, A; Kiss, G; Klimont, Z; Kolmonen, P; Komppula, M; Kristjansson, JE; Laakso, L; Laaksonen, A; Labonnote, L; Lanz, VA; Lehtinen, KEJ; Rizzo, LV; Makkonen, R; Manninen, HE; McMeeking, G; Merikanto, J; Minikin, A; Mirme, S; Morgan, WT; Nemitz, E; O'Donnell, D; Panwar, TS; Pawlowska, H; Petzold, A; Pienaar, JJ; Pio, C; Plass-Duelmer, C; Prevot, ASH; Pryor, S; Reddington, CL; Roberts, G; Rosenfeld, D; Schwarz, J; Seland, O; Sellegri, K; Shen, XJ; Shiraiwa, M; Siebert, H; Sierau, B; Simpson, D; Sun, JY; Topping, D; Tunved, P; Vaattovaara, P; Vakkari, V; Veefkind, JP; Visschedijk, A; Vuollekoski, H; Vuolo, R; Wehner, B; Wildt, J; Woodward, S; Worsnop, DR; van Zadelhoff, GJ; Zardini, AA; Zhang, K; van Zyl, PG; Kerminen, VM; Carslaw, KS; Pandis, SN
2011 | Atmos. Chem. Phys. | 11 (24) (13061-13143)
atmospheric sulfuric-acid , chemical-transport model , ion-induced nucleation , mixed-phase clouds , nuclei number concentration , particle formation events , pure component properties , saturation vapor-pressures , secondary organic aerosol , simulation chamber saphir

In this paper we describe and summarize the main achievements of the European Aerosol Cloud Climate and Air Quality Interactions project (EUCAARI). EUCAARI started on 1 January 2007 and ended on 31 December 2010 leaving a rich legacy including: (a) a comprehensive database with a year of observations of the physical, chemical and optical properties of aerosol particles over Europe, (b) comprehensive aerosol measurements in four developing countries, (c) a database of airborne measurements of aerosols and clouds over Europe during May 2008, (d) comprehensive modeling tools to study aerosol processes fron nano to global scale and their effects on climate and air quality. In addition a new Pan-European aerosol emissions inventory was developed and evaluated, a new cluster spectrometer was built and tested in the field and several new aerosol parameterizations and computations modules for chemical transport and global climate models were developed and evaluated. These achievements and related studies have substantially improved our understanding and reduced the uncertainties of aerosol radiative forcing and air quality-climate interactions. The EUCAARI results can be utilized in European and global environmental policy to assess the aerosol impacts and the corresponding abatement strategies.

Measured Elemental Carbon by Thermo-Optical Transmittance Analysis in Water-Soluble Extracts from Diesel Exhaust, Woodsmoke, and Ambient Particulate Samples

2010 | J Occup Environ Hyg | 7 (1) (35-45)
combustion , niosh method 5040 , occupational exposure , residential woodburning

Elemental carbon has been proposed as a marker of diesel particulate matter. The objective of this study was to investigate if water-soluble carbonaceous compounds could be responsible for positive bias of elemental carbon using NIOSH Method 5040 with a thermo-optical carbon transmittance analyzer. Filter samples from eight different aerosol environments were used: pure diesel exhaust fume with a high content of elemental carbon, pure diesel exhaust fume with a low content of elemental carbon, pure biodiesel exhaust fume, pure woodsmoke, an urban road tunnel, an urban street canyon, an urban background site, and residential woodburning in an urban area. Part of each filter sample was analyzed directly with a thermo-optical carbon analyzer, and another part was extracted with water. This water-soluble extract was filtered to remove particles, spiked onto filter punches, and analyzed with a thermo-optical transmittance carbon analyzer. The ratio of elemental carbon in the watersoluble extract to the particulate sample measurement was 18, 12, and 7%, respectively, for the samples of pure woodsmoke, residential woodburning, and urban background. Samples with diesel particulate matter and ambient samples with motor exhaust detected no elemental carbon in the water-soluble extract. Since no particles were present in the filtered watersoluble extract, part of the water-soluble organic carbon species, existing or created during analysis, are misclassified as elemental carbon with this analysis. The conclusion is that in measuring elemental carbon in particulate aerosol samples with thermo-optical transmittance analysis, woodsmoke, and biomass combustion samples show a positive bias of elemental carbon. The water-soluble EC could be used as a simple method to indicate other sources, such as wood or other biomass combustion aerosol particles.

Time span and spatial scale of regional new particle formation events over Finland and Southern Sweden

Hussein, T.; Junninen, H.; Tunved, P.; Kristensson, A.; Dal Maso, M.; Riipinen, I.; Aalto, P.P.; Hansson, H.-C.; Swietlicki, E.; Kulmala, M.
2009 | Atmos. Chem. Phys. | 9 (14) (4699-4716)
aerosol formation , air-mass history , atmosphere , back trajectories analysis , continental boundary-layer , evolution , growth , nucleation events , number size distributions , smear-ii

We investigated the time span and spatial scale of regional new particle formation (NPF) events in Finland and Southern Sweden using measured particle number size distributions at five background stations. We define the time span of a NPF event as the time period from the first moment when the newly formed mode of aerosol particles is observable below 25 nm until the newly formed mode is not any more distinguishable from other background modes of aerosol particles after growing to bigger sizes. We identify the spatial scale of regional NPF events based on two independent approaches. The first approach is based on the observation within a network of stationary measurement stations and the second approach is based on the time span and the history of air masses back-trajectories. According to the second approach, about 60% and 28% of the events can be traced to distances longer than 220 km upwind from where the events were observed in Southern Finland (Hyytiala) and Northern Finland (Varrio), respectively. The analysis also showed that the observed regional NPF events started over the continents but not over the Atlantic Ocean. The first approach showed that although large spatial scale NPF events are frequently observed at several locations simultaneously, they are rarely identical (similar characteristics and temporal variations) due to differences in the initial meteorological and geographical conditions between the stations. The growth of the newly formed particles during large spatial scale events can be followed for more than 30 h where the newly formed aerosol particles end up in the Aitken mode (diameter 25-100 nm) and accumulation mode size ranges (diameter 0.1-1 mu m). This study showed clear evidence that regional NPF events can pose a significant source for accumulation mode particles over the Scandinavian continent provided that these findings can be generalized to many of the air masses traveling over the European continent.

Introduction: European Integrated Project on Aerosol Cloud Climate and Air Quality interactions (EUCAARI) – integrating aerosol research from nano to global scales (vol 9, pg 2825, 2009)

Kulmala, M.; Asmi, A.; Lappalainen, H.K.; Carslaw, K.S.; Poschl, U.; Baltensperger, U.; Hov, O.; Brenguier, J.L.; Pandis, S.N.; Facchini, M.C.; Hansson, H.-C.; Wiedensohler, A.; O'Dowd, C.D.
2009 | Atmos. Chem. Phys. | 9 (10) (3443-3444)

Contact information

Visiting addresses:

Geovetenskapens Hus,
Svante Arrhenius väg 8, Stockholm

Arrheniuslaboratoriet, Svante Arrhenius väg 16, Stockholm (Unit for Analytical and Toxicological Chemistry)

Mailing address:
Department of Environmental Science and Analytical Chemistry (ACES)
Stockholm University
106 91 Stockholm

Press enquiries should be directed to:

Stella Papadopoulou
Science Communicator
Phone +46 (0)8 674 70 11