Turbulence measurements performed in the North Atlantic during the James Cook cruise JC087, March 2013

During the cruise the turbulence probe MSS050 was used for microstructure measurements. The profiler is produced by Sea and Sun Technology GmbH in co-operation with ISW Wassermesstechnik. The probe was equipped with 2 velocity microstructure shear sensors, a microstructure temperature sensor, standard CTD sensors for precision measurements, a vibration control sensor, a two component tilt sensor, a fluorescence sensor and surface detection sensor (SD) to indicate the water surface hit at rising measurements. The sampling rate for all sensors is 1024 samples per second, the resolution 16 bit. During the MSS measurements, the ship was moving with speed approx. 0.5-1.0 knots with respect to the water against the wind. In order to take into account the intermittent nature of marine turbulence, repeated MSS measurements were carried out in bursts of typically 10 profiles per station. The measurement interval was approximately 7 (10) min for a profile to 140 (200) dbar. During JC87 cruise 8 series of turbulence measurements were conducted. Fluorescence data was obtained on the 5 of them.

Seismic Data from MSM21/4 to Knipovich Ridge on the western Svalbard margin

The seismic data were acquired north of the Knipovich Ridge on the western Svalbard margin during cruise MSM21/4. They were recorded using a Geometrics GeoEel streamer of either 120 channels (profiles p100-p208) or 88 channels (profiles p300-p805) with a group spacing of 1.56 m and a sampling rate of 2 kHz. A GI-Gun (2×1.7 l) with a main frequency of ~150 Hz was used as a source and operated at a shot interval of 6-8 s. Processing of profiles p100-p208 and p600-p805: Positions for each channel were calculated by backtracking along the profiles from the GI-Gun GPS positions. The shot gathers were analyzed for abnormal amplitudes below the seafloor reflection by comparing neighboring traces in different frequency bands within sliding time windows. To suppress surface-generated water noise, a tau-p filter was applied in the shot gather domain. Common mid-point (CMP) profiles were then generated through crooked-line binning with a CMP spacing of 1.5625 m. A zero-phase band-pass filter with corner frequencies of 60 Hz and 360 Hz was applied to the data. Based on regional velocity information from MCS data [Sarkar, 2012], an interpolated and extrapolated 3D interval velocity model was created below the digitized seafloor reflection of the high-resolution streamer data. This velocity model was used to apply a CMP stack and an amplitude-preserving Kirchhoff post-stack time migration. Processing of profiles p400-p500: Data were sampled at 0.5 ms and sorted into common midpoint (CMP) domain with a bin spacing of 5 m. Normal move out correction was carried out with a velocity of 1500 m s-1 and an Ormsby bandpass filter with corner frequencies at 40, 80, 600 and 1000 Hz was applied. The data were time migrated using the water velocity.

Physical water column observations during summer breeze winds

During summer seasons (from 2012 to 2015) high resolution observation were performed in the Civitavecchia coastal area (Northern Tyrrhenian sea, west coast). All sampling was carried out from a small boat (5m rigid inflatable) starting in the early morning typically around 06:00 a.m. , and lasting from 2 to 8 h, depending on the weather conditions. The purposes of the experiment was to observe the variations of both the coastal circulation and the water column in response to rotation of 180 ° in the wind direction. During surveys both current measurements and yo-yo time series were performed. Current data were acquired using an ADCP SonTeck (500 Khz, sampling interval from 20sec to 60 sec, average interval 50% sampling, cell thickness 1 meter) and the yo-yo time series employing a small instrument package (CTD). The CTD contained an Idronaut 316 Plus and a SeaPoint fluorometer. The sampling rate for the CTD was 10Hz, profiling with the CTD was done by allowing the instrument package to free-fall, at an average descent rate of 1 m/s. During the summer 2012, the sampling plan consisted in four stations spaced a quarter of a mile (St. 1 - 10 m; St. 2 - 20 m; St. 3 - 30 m; and St. 4 - 40 m), in which yo-yo time series were performed with an interval of 20 min. In order to study fluorescence of Chlorophyll a pathes distribution in coastal zone. Breeze induced circulation was the goal of the following summers surveys, in these current measurements and yo-yo time series were performed moored at a depth of 40 m. Offshore station (St. 1 -40m) has been chosen to perform measurement, basis of previously observations (2012 sampling surveys). It was decided as wind driven circulation and mixing phenomena are less influenced by seabed than the other stations. Acquired data have been processed by NEMO SeaDataNet software.

Description of sampling sites in Northern Russia

The youngest ice marginal zone between the White Sea and the Ural mountains is the W-E trending belt of moraines called the Varsh-Indiga-Markhida-Harbei-Halmer-Sopkay, here called the Markhida line. Glacial elements show that it was deposited by the Kara Ice Sheet, and in the west, by the Barents Ice Sheet. The Markhida moraine overlies Eemian marine sediments, and is therefore of Weichselian age. Distal to the moraine are Eemian marine sediments and three Palaeolithic sites with many C-14 dates in the range 16-37 ka not covered by till, proving that it represents the maximum ice sheet extension during the Weichselian. The Late Weichselian ice limit of M. G. Grosswald is about 400 km (near the Urals more than 700 km) too far south. Shorelines of ice dammed Lake Komi, probably dammed by the ice sheet ending at the Markhida line, predate 37 ka. We conclude that the Markhida line is of Middle/Early Weichselian age, implying that no ice sheet reached this part of Northern Russia during the Late Weichselian. This age is supported by a series of C-14 and OSL dates inside the Markhida line all of >45 ka. Two moraine loops protrude south of the Markhida line; the Laya-Adzva and Rogavaya moraines. These moraines are covered by Lake Komi sediments, and many C-14 dates on mammoth bones inside the moraines are 26-37 ka. The morphology indicates that the moraines are of Weichselian age, but a Saalian age cannot be excluded. No post-glacial emerged marine shorelines are found along the Barents Sea coast north of the Markhida line.

Flower and seed biomass, and germination rate of arctic tundra plants in response to long term experimental warming

We provide new information on changes in tundra plant sexual reproduction in response to long-term (12 years) experimental warming in the High Arctic. Open-top chambers (OTCs) were used to increase growing season temperatures by 1-2 °C across a range of vascular plant communities. The warming enhanced reproductive effort and success in most species; shrubs and graminoids appeared to be more responsive than forbs. We found that the measured effects of warming on sexual reproduction were more consistently positive and to a greater degree in polar oasis compared with polar semidesert vascular plant communities. Our findings support predictions that long-term warming in the High Arctic will likely enhance sexual reproduction in tundra plants, which could lead to an increase in plant cover. Greater abundance of vegetation has implications for primary consumers - via increased forage availability, and the global carbon budget - as a function of changes in permafrost and vegetation acting as a carbon sink. Enhanced sexual reproduction in Arctic vascular plants may lead to increased genetic variability of offspring, and consequently improved chances of survival in a changing environment. Our findings also indicate that with future warming, polar oases may play an important role as a seed source to the surrounding polar desert landscape.

Sampling data, experimental data and fecal pellet characteristics of water pump samples in the strait of Øresund between Denmark and Sweden during 2004/2005

Copepod fecal pellets are often degraded at high rates within the upper part of the water column. However, the identity of the degraders and the processes governing the degradation remain unresolved. To identify the pellet degraders we collected water from Øresund (Denmark) approximately every second month from July 2004 to July 2005. These water samples were divided into 5 fractions (<0.2, <2, <20, <100, <200 µm) and total (unfractionated). We determined fecal pellet degradation rate and species composition of the plankton from triplicate incubations of each fraction and a known, added amount of fecal pellets. The total degradation rate of pellets by the natural plankton community of Øresund followed the phytoplankton biomass, with maximum degradation rate during the spring bloom (2.5 ± 0.49 d**-1) and minimum (0.52 ± 0.14 d**-1) during late winter. Total pellet removal rate ranged from 22% d**-1 (July 2005) to 87% d**-1 (May). Protozooplankton (dinoflagellates and ciliates) in the size range of 20 to 100 µm were the key degraders of the fecal pellets, contributing from 15 to 53% of the total degradation rate. Free-living in situ bacteria did not affect pellet degradation rate significantly; however, culture-originating bacteria introduced in association with the pellets contributed up to 59% of the total degradation rate. An effect of late-stage copepod nauplii (>200 µm) was indicated, but this was not a dominating degradation process. Mesozooplankton did not contribute significantly to the degradation. However, grazing of mesozooplankton on the pellet degraders impacts pellet degradation rate indirectly. In conclusion, protozooplankton seems to include the key organisms for the recycling of copepod fecal pellets in the water column, both through the microbial loop and, especially, by functioning as an effective 'protozoan filter' for fecal pellets.