15 10 10 Temperature (oC) Temperature (oC) 5 0 -5 -10 -15 Summer (J, J, A) Winter/coldest months (J, F, M) Mean annual air temperature -20 -25 1992 1996 2000 2004 2008 2012 2016 Figure 2. Annual mean air temperatures at Arctic Station from 1992 to 2018 and mean air temperatures for the warmest months (June, July and August) and the coldest months (January, February and March). Weather and Climate Monitoring Arctic Station has monitored local meteorological parameters since 1991. The old automatic weather station was removed in 2018, but measurements of similar parameters are continued at the nearby weather station in Østerlien where data has been collected since 2012 (Figure 1). Most of the data shown in this section are from these two weather stations. Several smaller temperature- or weather stations are located at different elevations in the area to cover altitudinal gradients and local variability. The annual mean air temperature in 2018 was -3.2C (Figure 2). It was a year with average winter temperatures and relatively low summer temperatures when compared to the period of registration (1991-2018). Particularly, June and July were cold with mean monthly air temperatures being the lowest since 1999 and 2004, respectively (Figure 3). The warmest day was registered on 6 June when a dr y warm Foehn wind from the East increased the air temperature from a few degrees to 17C (Figure 6). During the rest of the summer, the temperature never exceeded 15C (Figure 4). No negative air temperatures were registered from 13 June to 20 September. Foehn situations are common in this area and can happen any time a year. When they occur in the winter time, snow melt and subsequent re-freezing can result in ice covers depending on the duration and maximum temperature of these warm episodes. When the snow cover disappears the insulating effect also disappear and air temperature can easier affect the soil. Two significant Foehn situations were obser ved in March. Another Foehn situation with positive temperatures lasted for a period of 35 hours and reached a maximum temperature of 9 degrees on 19 and 20 November 2018. This caused massive snow melt illustrated in the snow data from Østerlien (Figure 4). Several freeze-thaw cycles were obser ved in April and May. 5 0 -5 -10 AVG -15 Min -20 2018 Max -25 -30 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Figure 3. Mean monthly air temperatures in 2018 compared to minimum, maximum and average values for the period 1992-2018. The summer was also relatively wet with cloudy conditions. Rain was registered on 31 out of 62 days in July and August. A heav y rain- event occurred on the 3 August when 66 mm of rain was registered (Figure 4). Peak water levels and increased discharge rates were obser ved in R øde Elv during this event (Figures 9 and 10). In total 281 mm rain was registered from 1 May to 30 September which placed 2018 in the high end compared to rain measured over the last decades (Figure 5). Total annual precipitation includ ing both snow and rain was measured at Teleøen approximately 70 0 meter from Arc tic Station as par t of A siaqs ClimateBasis program. The relatively cold and wet summer caused slower thaw penetration into the ground and lower soil temperatures compared to earlier years. It also re sulted in water saturated soil conditions during most of the summer (Figure 4). Gas exchange monitoring Measurements of carbon dioxide (CO 2 ) exchange rates bet ween land and atmosphere have been re corded in Østerlien since November 2012. Østerlien is a relatively moist area covered by low vegetation of dwar f shrubs. Data is continuously collec ted using an eddy covariance system consisting of an ultrasonic 3D anemometer and an infrared gas analy zer. The location nex t to Arc tic Station makes year-round measurements possible, because the instruments are powered by cables from the station and permanent staf f is available to ser vice the station throughout the winter. Uptake of CO 2 by photosynthesis exceeded the re lease of CO 2 by respiration from the 22 June. There by, the ecosystem turned into a sink of CO 2 with a net uptake from the atmosphere to the land sur face (Figure 4). The system switched back to a net source of CO 2 by the end of August when leaf senescence gradually ended the photosynthesis. The peak uptake rate was reached on 19 July. A n n u a l R e p o r t 2018 7 university of copenhagen facu lt y of sci e nc e A RC T I C STAT I ON Ann ual Repor t 2 018 2 A R C T I C S TAT I O N ARCTIC STATION Annual Report 2018 CONTENTS Chairmans welcome ............................................................ 5 Monitoring at Arctic Station ........ .......................................... 6 Research projects ........................ ......................................... 17 Educa 4 Chairmans Welcome Professor Bo Elberling Compared to other years, the summer of 2018 was cold and wet in Greenland. While summer temperatures in Europe were higher than for decades, summer temperatures at Arctic Station were in general low. Despite the weather, the year 2018 has been a very succes Monitoring at Arctic Station Charlotte Sigsgaard, Regin Rønn, Michele Citterio, Jakob Abermann, Per Juel Hansen, Kirsty Langly, Kirsten S. Christoffersen, Sille Myreng, Daniel Binder, Laura Helene Rasmussen, Morten Rasch, Aart Kroon, Dorthe Krause-Jensen, Birgit Olesen, Thomas Friborg and Bo Elberli 15 10 10 Temperature (oC) Temperature (oC) 5 0 -5 -10 -15 Summer (J, J, A) Winter/coldest months (J, F, M) Mean annual air temperature -20 -25 1992 1996 2000 2004 2008 2012 2016 Figure 2. Annual mean air temperatures at Arctic Station from 1992 to 2018 and mean air temperatures for 31-J an 2-Mar 1-Apr 1-May 31-May 30-J un 30-J ul 29-Aug 28-S ep 28-Oct 27-Nov 27-Dec 2018 1040 1000 960 60 0 40 -10 20 -30 0 Wind speed (m s -1) -20 Rain (mm) 80 10 Temperature (C) Air pressure (mbar) 1-J an 16 12 8 4 0 Wind dir () 300 200 100 S now depth (m) 0 0.8 40 0 Sep Precipitation (mm) 350 Aug Jul Jun May 30 0 250 20 0 150 10 0 50 19 91 19 92 19 93 19 94 19 95 19 96 19 97 19 98 19 99 20 00 20 01 20 02 20 03 20 04 20 05 20 06 20 07 20 08 20 09 20 10 20 11 20 12 20 13 20 14 20 15 20 16 20 17 20 18 0 Figure 5. Stacked monthly values of rain from Figure 7. Water started to run in the snow covered river bed on 6 June. Several fows with a mixture of water, snow and ice occurred during the day. Photos: Charlotte Sigsgaard and Laura L. Frendrup. Marine monitoring Marine monitoring has been periodically carried out at Arc tic Station since 1924. Figure 9. About 60-70 mm of rain on the 3 August 2018 caused overland fow and high discharge and high content of suspended sediment in the river. Photo: Elisabeth L. Kolstad. there is of ten a layer of cold water at 50 -10 0 m with temperatures as low as -1.6 C sandwiched bet ween the warmer sur fa Macroalgae monitoring 8 7 10 m 50 m 200 m The Greenland Ecosystem Monitoring program (GEM) on marine vegetation in the Disko Bay was initiated in the summer of 2018. The program includes studies of tidal and subtidal macroalgae along the shores of Disko Island and Kronprinsens Ejland as specified Figure 13. Overview, based on drone images, of Fortuna Bay with the tidal vegetation forming a fringe along the shoreline visible as a light brown contour at low tide. Drone operated by Dorte KrauseJensen and Birgit Olesen and drone images analysed and processed by Michael Bo Rasmussen. Growth of s 14 Chlorophyll (ug l-1) 12 Danish Meteorological Institute (DM I) which will pro vide data for in-situ validation data for DM Is remote sensing produc t s. The first complete dataset will be downloaded in 2019. Data received via satellite link already shows seasonal variabilit y in the temperatur Figure 18. Two moulins on Chamberlin Glacier found in August 2018 (left) and the entrance of one of the moulins which in August 2018 appeared safe to descend. Photos: Michele Citterio. Influence of cloud cover in surface energy balance in Arctic environments Sur face air temperatures in the Arctic enhance snow and glacier melt is still poorly known, not the least in Greenland. While some authors claim clouds enhance melt water runof f others claim that decreasing cloud cover drives the recent mass loss on the Greenland ice sheet. Despite their crucial impor tance for understanding Arc tic cli Research Projects Development of methodology for evaluating chemicals discarded in high Arctic waters Kim Gustavson, Eva Friis Møller, Mette Dalgaard, DCE, Department of Bioscience Aarhus University, Denmark The overall aim of the project was to strengthen the basis for evaluation and regulation of Baleen whale. Photo: Mads Peter Heide-Jørgensen. Qimmeq Anders J. Hansen, Tom Gilbert, University of Copenhagen, Denmark, Nobuyuki Yamaguchi, Qatar University, Quatar, Siz Madsen, Denmark The Qimmeq Project consists of several components including, sled dog genetics, culture history, film- and phot Greenlandic Perspectives Survey (GPS) AMAP - collection of ring seal samples Kelton Minor, University of Copenhagen, Kraks Fond Institute for Urban Economic Research, Denmark, Ulunnguaq Markussen, University of Greenland, Greenland, Hans Peter Mønsted, University of Southern Denmark, Denmark Sign CENPERM activities Per Ambus, Anders Michelsen, Laura Helene Rasmussen, Laura Bjørnholt Larsen, Emily Pickering Pedersen, Ludovica D'Imperio, Andreas Westergaard-Nielsen, Trevor James Popp, Steffen Bo Hansen, Sune Olander Rasmussen, Bo Elberling, University of Copenhagen, Denmark, Peter Convey, Brit A n n u a l R e p o r t 2018 21 Preparing samples in the laboratory . Photo: Advanced Analytical Chemistry - Arctic Pollution Chemistry 2018 (Field course) Photo Kent Pørksen 22 Education CHESS PhD school: Arctic Glacier Field Course Alexios Theofilopoulos, Andreas Alexander, Anais Bretones, Andreas Plach, Calvin Shackleton, Ida Margrete Ringgaard, Jacob Morgan, Jonathan Rheinlander, Karita Kajanto, Lis Allaar t, Margaret Lindeman, Maya Becker, Mor ven Muilwijk, Nicholas Ra Field trip North Greenlands High School GUX Asiaat Photo: Advanced Analytical Chemistry -Arctic Pollution Research 2018 (Field course). All projec ts included numerous sampling trips in the field (open water and coast line) followed by analyses in dif ferent designated labs at the Arc tic Station based monitoring projec t focusing on the conditions of the living resources based on input from local fishers and hunters. Visiting period: 5 December, 2 days. Climate Change in Greenland Niels Vinther, Egedal Gymnasium, A sger Vinther Michelsen, Kenneth Sorento, Mediehuset København Denmark Visit Publications Scientific papers 2018 A lb e r s C. N ., K ra m s h ø j M ., R inna n R . (2018). R a p i d min e ra liz at i o n of b i o g e ni c vo lat il e o rg a ni c co m p o un d s in te m p e rate a n d A rc t i c s o ils . B i o g e o s ci e n ce s 15, 3591-3 6 01. D O I :10.519 4 / b g -15 - Reports 2018 K a li t a, S . N ., Wo hlra b, S ., Ku e hn e, N . a n d J o hn, U., A l fre d - We g e n e r- I ns t i tu te (2018): Tra ns c r ipto m e ana l y s is of sing l e ce lls: a p la nk to n cha ra c te r iz at i o n of A rc t i c wate r s , 2n d A nnua l M e e t ing of D F G -S P P 19 91 T Members of the board Professor Anders Michelsen Depar tment of Biology Phone: + 45 2339 8286 E-mail: andersm@bio.ku.dk Professor Bo Elberling (Chairman) Depar tment of Geosciences and Natural Resource Management Phone: + 45 3532 2520 E-mail: be@ign.ku.dk A ssociate Professor Nina Lundholm Natural A n n u a l R e p o r t 2018 29 Title Arc tic Station Annual Repor t 2018 Publisher Board of the Arc tic Station, Univer sit y of Copenhagen, Denmark Editor A ar t Kroon and Charlot te Sigsgaard L ayout and graphic s Kent Pørk sen, Depar tment of Geosciences and Natural Resource Management Internet ver sion ark tisk station.ku.dk