Typically surfing brings to mind sandy beaches, warm water, and blue waves. The Arctic Surfers, however, put surfing in a new light. The group provides stand-up paddle board and surf retreats in Iceland, including in the Glacier Lagoon and on the Reykjanes Peninsula.
Surfers wait for the perfect moment to ride the waves that occur when part of a glacier calves into the ocean, creating Arctic-style big-wave conditions. Garett McNamara and Kealii Mamala, two surfers, set to be the first people to surf a glacier.
This photo Friday enjoy some photos from the Arctic Surfers’s adventures in Iceland.
Jellyfish can often be found in abundance in communities living in the benthic boundary layer, the water directly above the seafloor. The cold high-latitude systems surrounding the poles are no exception. A recent studypublished by Grange et al. in PLOS One reports on unusually high abundances of Ptychogastria polaris Allman in fjords in the glacier-rich West Antarctic Peninsula.
P. polaris is a cold-water species that has been found in a variety of locations in the high latitudes of the Northern and Southern Hemisphere. It was first described in 1878 by A.G. Allman, based on a single specimen collected off East Greenland. Since then, it has been found to have a patchy, circumpolar distribution in Arctic and sub-Arctic areas, while only a few specimens have been documented in Antarctica.
Between January and February 2010, Grange et al. conducted surveys of benthic megafauna in three subpolar fjords along the West Antarctic Peninsula – Andvord, Flandres and Barilari Bays.
“Arctic fjords are heavily impacted by meltwater inputs and sedimentation that yield low seafloor abundance and biodiversity, so we wanted to see if that was also the case in the Antarctic,” Grange explained to GlacierHub.
They analyzed live specimens, conducted photosurveys of the seafloor, and measured background environmental conditions to gain a better understanding of the distribution of P. polaris. Molecular analysis and DNA sequencing were also used to confirm the species identifications of specimens.
P. polaris was found to be a common component of seafloor communities in both Andvord and Flandres Bays, but was absent in Barilari Bay. “We noted the conspicuous occurrence and high abundance of P. polaris,” Grange stated. She noted that the densities in these locations up to 400 times higher than previously recorded in northeast Greenland and the Barents Sea.
These levels could be a result of higher productivity within the benthic boundary layer in the fjords. Reasons for this productivity include higher nutrient inputs that occur when the remains of sustained phytoplankton blooms sink to the ocean floor, or when macroalgae (large-celled algae such as seaweed) cascade down fjord walls, providing food sources that support larger populations of P. polaris. In addition, migrating Antarctic krill and baleen whales can transport nutrients to these regions in the form of feces and krill carcasses.
P. polaris was also observed in smaller densities in the water column in all three bays. Although this species is known to undertake short swimming expeditions of up to fifteen seconds, these observations were relatively frequent, suggesting that P. polaris in Antarctica may behave differently from counterparts in Arctic and boreal environments. This could be driven by feeding opportunities, localized regions of turbulent mixing at the seafloor, or distinct circulation patterns, but further research is needed, according to Grange et al.
Both findings also suggest that P. polaris may form a link between pelagic (open water) and benthic food-webs within the region. For example, they may play an important role as ecological predators of benthic organisms like zooplankton, while providing food inputs to the seafloor when they die. This contributes to nutrient and energy transfers between the ecosystems, helping to integrate the dynamics of food-webs in different layers of the marine environment.
This study was also the first to provide a phylogenetic (evolutionary history and relationship) analysis of the Ptychogastriidae family, to which P. polaris belongs. “We found relatively large genetic differentiation among P. polaris compared to that for other hydrozoan (the larger taxonomic class of organisms) species,” Grange explained. “This discovery may suggest the species contain multiple cryptic species (different species with identical physical forms) or an unusually high degree of sequence variation between the extreme ends of its distributional range.”
Further research will help to elucidate the findings of this study. The complex interplay between wind, tidal and glacial processes in subpolar fjords also creates a variety of conditions in different fjords, suggesting that glacier-related environments such as these may yield more surprising discoveries.
There are numerous harbor seals (Phoca vitulina) living in tidewater glacier fjords in Alaska. Harbor seals are covered with short, stiff, bristle-like hair. They reach five to six feet (1.7-1.9 m) in length and weigh up to 300 pounds (140 kg). Tidewater glaciers calve icebergs into the marine environment, which then serve as pupping and molting habitat for harbor seals in Alaska. Although tidewater glaciers are naturally dynamic, advancing and retreating in response to local climatic and fjord conditions, most of the ice sheets that feed tidewater glaciers in Alaska are thinning. As a result, many of the tidewater glaciers are retreating. Scientists are studying the glacier ice and distribution of harbor seals to understand how future changes in tidewater glaciers may impact the harbor seals. Jamie Womble, a marine ecologist based in Alaska, is one of them.
As Womble put in her recently published paper in PLOS One, “The availability and spatial distribution of glacier ice in the fjords is likely a key environmental variable that influences the abundance and distribution of selected marine mammals; however, the amount of ice and the fine-scale characteristics of ice in fjords have not been systematically quantified. Given the predicted changes in glacier habitat, there is a need for the development of methods that could be broadly applied to quantify changes in available ice habitat in tidewater glacier fjords.”
To conduct her research, Womble has used a variety of analytical tools including geospatial modeling (GIS), multivariate statistics, and animal movement models to integrate behavioral and diet data with remotely-sensed oceanographic data. Most recently, she has worked with object-based image analysis (OBIA).
“OBIA is a powerful image classification tool. Many people studying forests and urban areas use it,” Anupma Prakash, a colleague of Womble and professor of geophysics at the University of Alaska, told GlacierHub. “In our case, we could not use the satellite images because the satellite images did not have the details we required. We flew our aircraft quite low so we saw a lot of detail and could identify individual icebergs.”
OBIA offers an enhanced ability to quantify the morphological properties of habitat. Satellite imagery, on the other hand, is not a viable method in Alaska as there are few cloud free days.
“We wanted to classify our images into water, iceberg, and brash-ice (small pieces of ice and water all smushed together),” Prakash added. “The color and smoothness of water helped us isolate it. For icebergs the color, shape, and angular nature helped us isolate it, and the rest was bash-ice.” So it is now feasible to quantify fine-scale features of habitats in order to understand the relationships between wildlife and the habitats they use.
Thanks to the work of scientists like Womble and Prakash, OBIA can now be applied to quantify changes in available ice habitat in tidewater glacier fjords. The method can also introduced in other geographic areas, according to professor Prakash. Now that there is a more advanced method to study the harbor seals in Alaska, the hope is that other researchers will use the OBIA method to make further discoveries about key ocean habitats.
Most people think of algae as the bothersome green stuff that grows on the tops of ponds and needs to be removed from the inside of fish tanks, but algae also provides clues about the environment. The response of Harmful Algal Blooms (HABs) to climate change, for example, provides evidence that some algae are extremely efficient environmental adaptors.
HABs are formed when colonies of algae living in fresh or saltwater grow out of control and begin producing toxic effects that can threaten the health and lives of animals and humans. According to NOAA, they have occurred in every coastal state in the United States and are increasing in frequency due to rising temperatures associated with climate change. As a result, HAB responses to climate change, including changes in pH and CO2, have been increasingly studied.
These responses include the expansion of the blooms into larger areas and an increased release of toxic poisons with warming temperatures. In a recently published paper, Mardones et al examine a special type of algal bloom found to be an expert adaptor to climate change. This strain of algal blooms called Alexandrium catenella occurs in highly variable fjord systems in southern Chile.
These Chilean fjords have had to respond to fluctuations in CO2 and pH. They experience huge freshwater inputs from Patagonian ice fields and heavy precipitation events. When dissolved in water, CO2 forms carbonic acid, which has a low pH. Therefore, levels of CO2 and pH are inversely correlated. As CO2 increases due to climate change, algal blooms in the fjords produce more Paralytic Shellfish Toxin (PST). This toxin could have long-term effects on the fish population and therefore the entire food web and ecosystem in the fjord.
In an article by Pedro Costa, he describes how these neurotoxins can have a lasting impact: poisoned fish can be consumed by seals and humans, causing health issues or even death. As we expect CO2 to continue to rise, it is very likely harmful algal blooms like the ones in Chile will produce more PST, leading to more fish kills, disturbed ecosystems in the fjords, and possible human health issues.
During their research, Mardones et al explored six levels of CO2/pH and two light conditions to examine how the algal blooms react. The scientists identified key differences in the waters in the fjord closest to the melting ice fields and the waters in the fjord further offshore. The near-shore water in the fjord experiences the largest impact of the freshwater inputs from the ice fields. The freshwater means that the upper layers of the water are much less salty compared to lower layers. This creates an intense halocline (stronger layers of differences in salinity) in the water column. Strong winds in the region mix the layers, which produce highly fluctuating differences in carbonate chemistry. As Patagonian glaciers continue to melt, even more freshwater will be introduced into the fjords, which will continue to change the conditions of the water.
On the other hand, the more stable offshore waters have CO2 equilibrium with the atmosphere. The main environmental driver offshore is human-caused ocean acidification. As CO2 emissions increase in the atmosphere, it dissolves in oceans and lowers the pH of the water. For most species, this causes huge problems, but certain types of algal blooms are able to adapt to these conditions.
Previous studies done by Tatter et al. show that a type of the same algal bloom from Southern California have previously changed their physiological responses due to changing pCO2/pH. Under higher CO2 conditions, production of Paralytic Shellfish Toxin increased. In 2015, there was an unprecedentedly large algal bloom that stretched from Central California to the Alaskan peninsula.
Mardones et al. found similar results in the Chilean algal blooms by examining the strains of the bloom under lab conditions. The blooms had been previously harvested years before and kept in culture. They analyzed these HAB responses to changes in pH and CO2. While they had optimal physiological performance at near-equilibrium levels of pH/CO2, the algal blooms showed an ability to adapt to changing conditions. They found that the blooms are in fact able to adapt their cell size based on the pH/ CO2 levels. In conditions with high pH/low CO2, the blooms adapted to a smaller cell size. In conditions with low pH/high CO2, their cell size increased, which means they are able to change their shape to not only survive changing conditions, but to thrive in them. In low CO2, high pH could increase chain formation (they could increase their swim speed to maintain their location without being moved in the current).
These factors, in addition to others, contribute to the resiliency of the harmful algal blooms in changing conditions, demonstrating they are expert adaptors to climate change.
Glacial Melt Pours Iron into Ocean, Seeding Algal Blooms
Scientists report in a new study this week that glacial melt may be funneling significant amounts of reactive iron into the ocean, where it may counter some of the negative effects of climate change by boosting algal blooms that capture carbon.
Fighter Pilot Films First Person View Of Flight Over Fjords
“Being a fighter pilot is a lot of work. Maintence, years of training, planning for missions, paperwork — all just to pilot one of the faster, deadlier machines ever created by human hands. Seems like a real hassle, right?”