Seasonal and Morphological Controls on Nitrate Retention in Arctic Deltas

Deon Knights, Anastasia Piliouras, Jon Schwenk, Jayaram Hariharan, Christopher Russoniello

Research output: Contribution to journalArticlepeer-review

3 Scopus citations


Estimates of nitrate loading to the Arctic Ocean are limited by the lack of field observations within deltas partly due to logistical constraints. To overcome this limitation, we use a remote sensing framework to estimate retention of nitrate in Arctic deltas. We achieve this by coupling hydrological and biogeochemical process models at the network scale for five major Arctic deltas. Binary masks of delta channels were used to simulate flow direction and magnitude through networks. Models were parameterized using historical and seasonal observations. Simulated nitrate retention ranged from 2.9% to 15% of the incoming load. Retention rates were largest during winter but smallest during spring conditions when increased discharges export large nitrate masses to the coast. Under future climate scenarios, retention rates fall by ∼1%–10%. Arctic deltas have an important effect on the magnitude of nitrate entering Arctic seas and the inclusion of processing in deltas can improve flux estimates.

Original languageEnglish (US)
Article numbere2022GL102201
JournalGeophysical Research Letters
Issue number7
StatePublished - Apr 16 2023

All Science Journal Classification (ASJC) codes

  • Geophysics
  • General Earth and Planetary Sciences

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