Front Page Detectives

Alaska's Arctic Rivers Turning Alarmingly Bright Orange Color, Raising Fears of Ecosystem Disaster

'Alarming' Phenomenon Turning Alaska's Rivers Bright Orange
Source: United States Geological Survey

An orange tributary of the Kugororuk River

Dec. 26 2023, Published 1:01 p.m. ET

Link to FacebookShare to XShare to Email

The pristine arctic rivers of Alaska are experiencing a striking transformation, as their once-clear waters are turning an alarmingly vivid orange hue, prompting concern among scientists.

The phenomenon is particularly pronounced in the Brooks Range, a sprawling 700-mile mountain range extending from northern Alaska into Canada's Yukon Territory. Over the past five to 10 years, at least 75 rivers and streams in this region have taken on a bright orange tint, according to Scientific American.

Article continues below advertisement

The leading explanation for the phenomenon points to climate change-induced thawing of permafrost. As per Scientific American, the discoloration results from oxidizing iron and sulfuric acid, indicating elevated concentrations of heavy metals in the rivers. The oxidation of minerals in the soil may also be reducing the water's pH, making it more acidic.

The consequences of the altered pH levels on the intricate river ecosystem remain uncertain, raising concerns among scientists about the potential leaching of toxic metals. This, in turn, could pose a threat to aquatic life and downstream communities that rely on these rivers for sustenance and drinking water.

Becky Hewitt, an environmental studies professor at Amherst College involved in investigating the phenomenon, expressed her concern over the pH issue, emphasizing its alarming nature, as reported by Popular Science.

While scientists have identified the mechanisms behind the rust-colored waters, the specific cause of contamination had been unclear until recently.

Article continues below advertisement

An ongoing study is seeking to document these occurrences, their timing and the factors contributing to them by analyzing stream chemistry and testing hypotheses related to their origin.

The United States Geological Survey is overseeing this research, which aims to explore the connections between warming and thawing landscapes, and the potential repercussions for downstream water quality and ecosystems.

Breaking News

The National Parks Service (NPS) emphasized the accelerated warming of the Arctic, outpacing other global regions, with significant consequences for both terrestrial and aquatic ecosystems.

Roman Dial, a researcher and professor of biology and mathematics at Alaska Pacific University, highlighted the severity of the issue, describing affected streams as not only stained but so acidic that they could “curdle your powdered milk,” Popular Science reported.

Article continues below advertisement

Never miss a story — sign up for the Front Page Detectives newsletter. Be on the scene the moment news breaks.

Despite initial suspicions of acid mine waste, researchers determined that the rusty discoloration originated from the land itself.

One theory attributes the phenomenon to acid-rock drainage, suggesting that permafrost thaw exposes bedrock, releasing sulfuric acid and iron. Another hypothesis, known as the "wetlands hypothesis," suggests that thaw-activated soil bacteria produce soluble iron, contributing to the rusty color.


Become a Front Page Detective

Sign up to receive breaking
Front Page Detectives
news and exclusive investigations.

More Stories

Opt-out of personalized ads

© Copyright 2024 Empire Media Group, Inc. Front Page Detectives is a registered trademark. All Rights Reserved. People may receive compensation for some links to products and services on this website. Offers may be subject to change without notice.