Canada’s Oceans Now: Arctic Ecosystems 2023 - From the land: nutrients and carbon entering the ocean

From the land: nutrients and carbon entering the ocean
Melting glaciers and permafrost both provide nutrients and carbon for the ocean. Their contributions influence food webs and CO₂ exchange in different ways.

This infographic is divided into two halves. The left half is titled “Western Arctic: nearshore permafrost melt”. Text below the title states:

• Permafrost melt is increasing, bringing more carbon to ocean waters.

Three diagrams below the text show different ways in which carbon is released into the ocean through melting permafrost.

Top diagram:

A vertical cross section of a coast is shown with high coastal cliffs to the left, and the ocean to the right. When the melting permafrost found within the high coastal cliffs melts slowly and forms mud, more CO₂ is released into the atmosphere, but this is done slowly over time. CO₂ is released when the mud stays nearshore and as it moves slowly into the ocean water. A text box in the top right states:

• Permafrost mud. More CO₂ is released, a slow release

Middle diagram:

A vertical cross section of a coast is shown with low coastal cliffs to the left, and the ocean to the right. When the melting permafrost causes parts of the cliff to collapse onto the beach, CO₂ is released into the atmosphere, and this is done quickly compared to the mud. The debris is pulled quickly by the waves into the ocean water moving the cliff material away from the nearshore.

A text box in the top right states:

• Cliff debris. Less CO₂ is released, a quick release

Bottom diagram:

A river is shown flowing from the land on the left into the ocean on the right. When the melting permafrost causes stored carbon to be released into the river, it then flows directly into the ocean.

A text box in the top right states:

• Rivers. Inland permafrost melt releases more carbon into the Mackenzie River, which flows into the Beaufort Sea.

The right half of the infographic is titled: “Eastern Arctic: glacier meltwater entering the ocean”.

Text below the title states:

• Glacier melt entering the ocean below the surface supplies nutrients in direct and indirect ways.

Below the text an image shows a glacier in the eastern Canadian Arctic next to the ocean.

Below the image, two side-by-side text boxes contain explanatory text on the direct (left) and indirect (right) ways glacier melts supply nutrients to the ocean:

• Direct: Glacier melt carries micronutrients like manganese (Mn). These nutrients can be tracked far from the glacier itself.
• Indirect: Glacier meltwater rises up, carrying ocean nutrients like nitrogen (NO^-₃) and phosphate (PO₄^3-) to the surface. Phytoplankton can use these nutrients.

Below the text boxes, on the bottom right corner, a diagram depicts the direct and indirect glacier melt nutrient sources explained above. On the left side of the diagram, a light blue glacier sits upon land with ocean water touching the side of the glacier. Melt water from the glacier containing manganese shown as small black dots flows out of the glacier. Melt water flowing from the glacier into the ocean floats up to the surface to form the meltwater layer (dark blue) at the surface. Nutrients (NO^-₃ and PO₄^3-) shown as dark orange dots are carried up with the melt water to the ocean surface. To the right of this meltwater layer, a light blue cloud of phytoplankton is located with the nutrients. These phytoplankton attract copepods, shown as t-shaped black silhouettes below the phytoplankton, which then attracts fish.