Boreal and subarctic lakes are subject to the climate‐sensitive process of browning, whereby transport of terrestrial dissolved organic matter (tDOM) to lakes results in greater dissolved organic carbon (DOC) concentrations and associated darker water color. Increasing tDOM will increase mercury (Hg) transport to these lakes, but whether this leads to greater methylHg (MeHg) bioaccumulation in food webs remains unclear. We det...

The Arctic is undergoing rapid environmental transformation, with intensified glacial and permafrost melt fundamentally altering freshwater discharge regimes and biogeochemical fluxes to coastal fjord systems. Here, we investigate how seasonal meltwater dynamics shape protistan plankton communities along a terrestrial – marine gradient in Isfjorden (Svalbard) during the exceptionally warm year of 2018. Sampling across three di...

Climate warming is especially pronounced in winter and at high latitudes. Warming winters are leading to the loss of lake ice and changing snow cover on lakes. Historically, lake scientists have paid less attention to the ice cover period, leading to data and theory gaps about the role of winter conditions in lake ecosystem function and the consequences of changing winters. Here we use simple models to show that the latitudina...

Seabirds are important vectors for nutrient transfer across ecosystem boundaries. In this seasonal study, we evaluate the impact of an Arctic colony (Alkhornet, Svalbard) of Black-legged Kittiwakes ( Rissa tridactyla ) and Brünnich’s Guillemots ( Uria lomvia ) on stream nutrient concentrations and fluxes, as well as utilization by coastal biota. Water samples from seabird-impacted and control streams were collected regularly t...

There is an urgent need to understand and address the risks associated with a warming climate for ecosystems and societies in the Arctic and sub-Arctic regions. There are major gaps in our understanding of the complex effects of climate change—including extreme events, cascading impacts across ecosystems, and the underlying socioecological dynamics and feedbacks—all of which need collaborative efforts to be resolved. Here, we...