The MarineBasis programme is running on its fifth year. Parameters are presented of sea ice conditions, physiochemical oceanography and biological studies of microscopic organisms up to the highest trophic levels. The continuous monitoring of this system will go beyond just providing a better understanding of high latitude marine systems and making it possible to observe and identify effects of climatic change in these regions.

Satellite imagery showed a seasonal pattern of sea ice coverage in Baffin Bay, which was comparable to previous years. Sea ice retreated northward in spring leaving no significant ice by mid-summer, before ice started building up again from the north during autumn. Inside Godthåbsfjord, less sea ice was observed than during most previous years, only the innermost parts of the fjord appear to have experienced sea ice coverage visible to satellite. Glacial ice and sea ice was exported from the fjord in seasonal bursts as it has been observed previously, but in 2010 glacial ice from Narssap Sermia fl owed unhindered out of the fjord as no sea ice was observed in front of the glacier. Thus, more icebergs reached Nuuk and fl owed out of the fjord as compared to previous years.

Vertical profiles of the water column showed a warm inflow of deep coastal water during winter followed by some of the highest temperatures and lowest salinities recorded in the surface waters during summer over the past five years. This surface layer also revealed high phytoplankton biomasses in summer leading to the second highest primary production peak measured since 2005. In contrast, the spring phytoplankton bloom appears to have been less pronounced than generally observed, which led to a more moderate decrease in nutrient levels in spring than usual. Nevertheless, nutrient exhaustion in the surface layer did subsequently take place during summer production. High pCO2 values (i.e. above atmospheric concentrations) observed during the latter part of 2009 continued into January 2010, producing the single highest recorded value during the programme. Aside from another smaller peak, pCO2 values during spring were generally lower than the year before, thus indicating that the fjord had regained some of its CO2 uptake capacity.

Phytoplankton showed a seasonal succession resembling the pattern observed in all years but 2009, with diatoms dominating community abundances throughout the year except during the spring bloom. Hence, Phaeocystis sp. was the most abundant algal species during spring bloom in all years, except in 2009 when they remained entirely absent. Copepods peaked a month earlier than generally observed, which coincided with the highest copepod nauplii abundance recorded during the programme. Microsetella sp. still dominated the copepod abundance in all but one month, when Microcalanus was most abundant. The large Calanus spp. was only present in significant numbers during the spring bloom. Other zooplankton than copepods also peaked during the summer production in July. Fish larvae showed highest abundances during spring in 2006-08, while they peaked during summer in 2009-10 due to a decrease in sand eel and an increase in capelin. Cod larvae were observed during spring and summer. Overall, the abundance of fish larvae has decreased since the start of the programme (i.e. 2006).

A length section from outside the fjord (Fyllas Banke) to the inner part of the fjord showed the highest fish larvae concentration at the entrance of the fjord (i.e. ‘Main station’) along with decreasing species diversity in the inner part of the fjord, as observed in previous years. Shellfish larvae were present from spring to summer and sand crab (Hyas sp.) and shrimp larvae (Pandalus sp.) showed almost twice the abundance as in 2008-09. Jellyfish were observed during winter and early spring while comb jellies (ctenophores) were present only from summer. While the length section showed crab and shrimp larvae to be present at all stations, abundances varied between stations along the length section and showed a significant inter-annual variation.

Sinking fluxes of particulate material followed the seasonal patterns in the pelagic production. Isotopic composition of the sinking material indicated a stronger terrestrial signal in autumn, likely to be caused by the higher discharge of freshwater. Total carbon sinking flux integrated over the year was comparable to the values estimated in previous years. A large part of the organic material that reaches the sediments is consumed and mineralized, partly to be returned to the water column as nutrients. Maximum oxygen consumption coincided with the summer peak in pelagic production and elevated temperatures, which is in contrast to most previous years where consumption peaked during the higher spring production.

The energetic status of one species of sea urchin and scallop is estimated using a condition index and gonad index. Scallops showed the highest gonad index in 2007 and 2010 and sea urchins in 2007 and 2009. Conditions indexes also vary significantly between years; scallops showed higher values in 2007 and sea urchins in 2009 and 2010. Inter-annual differences between species may be due to different spawning times and feeding strategies.

Monitoring of the large macroalgae species Laminaria longicruris (i.e. benthic flora) showed some of the highest recorded blade length and biomasses since 2007. Macroalgae sampling at two sites with different exposure, i.e. protected and exposed to sea ice in most years, does not show a consistent difference in growth rates. The time series rather do however reflect variation around an established average blade length and biomass.

Two major seabird colonies near Nuuk have been monitored since 2007, while other colonies in the area have been included later. One of the major colonies (Qeqertannguit) showed numbers of breeding kittiwakes, Iceland gulls and black-backed gull similar to previous years. This colony experiences egg harvesting. In 2007, no representative seabird counts were obtained from the Brünnich’s guillemot colony (Nunngarussuit). Surveys of Qegertannguit and four other colonies in the area seem to indicate movement of the kittiwakes and Iceland gull between the different colonies and that the four other colonies may likely prove important in the monitoring programme.

A photo-identification programme of humpback whales is used to estimate the minimum number of individuals entering Godthåbsfjord (i.e. out of the estimated 3000 humpback whales annually feeding in West Greenland waters). Since 2007, 52 different individuals have been identified, with 12 new individuals identified in 2010. Hence, the population is considered an open population where individuals move in and out during different seasons and years. While the re-sight rate of individuals from one year to the next is rather high, the re-sight rate of individuals in all four years is lower. Moreover, individual humpback whales repeatedly revisiting Godthåbsfjord seem to have a longer annual residence time within the fjord.