The Impact of Climate Change on Arctic Streams: The Rise of “Orange” Waters

May 26, 2024 / activist360

Tracking the effects of iron mobilization on stream food webs. Images of a headwater tributary of the Akillik River in Kobuk Valley National Park, Alaska, illustrating a shift from clearwater on June 12, 2017 (a) to orange stream conditions on August 30, 2018 (b). The blue arrows point to the same boulder near the confluence. c Stream food web data collected in before (September 2017) and after (September 2018) the color change demonstrates the reduction in benthic biofilmproduction, corresponding decline in benthic macroinvertebrate density, and a complete loss of resident fish (DV = Dolly Varden, SS = Slimy Sculpin). The open white circles in (c) represent observations where species absence was documented.

The Arctic is experiencing profound environmental changes due to climate change, with significant alterations in watershed hydrology and biogeochemistry. Hydrology is the scientific study of the movement, distribution, and management of water. Biogeochemistry is the scientific study of the chemical, physical, geological, and biological processes and reactions that govern the composition of the natural environment.

A recent study highlights a concerning phenomenon: the discoloration of streams in Alaska’s Brooks Range, turning from clear to orange. This discoloration is attributed primarily to increased concentrations of iron and toxic metals, a direct result of permafrost thaw.

Permafrost Thaw and Metal Mobilization

Permafrost, perennially frozen ground that has remained so for two or more consecutive years, is a crucial component of the Arctic ecosystem. It acts as a massive reservoir for organic carbon and metals, which, when thawed, begin to mobilize into the watershed. The study documents that this thawing, exacerbated by rapid warming and increased snowfall over the last decade, is leading to the rusting of Arctic streams, visible in their striking orange coloration. This discoloration is primarily due to the mobilization of iron (Fe) and other metals through the process of sulfide mineral weathering.

Impact on Water Quality

The transition of these streams from clear to orange is not just a superficial change. It reflects a significant degradation in water quality, characterized by lower pH levels, higher turbidity, and increased concentrations of sulfate, iron, and trace metals. These environmental shifts pose a considerable risk to the aquatic ecosystems and the species that depend on them. The research indicates dramatic declines in macroinvertebrate diversity and fish abundance in affected streams, pointing to a broader ecological crisis.

Biological Consequences

The biological impact of these changes is profound. The study notes a marked decrease in the diversity and abundance of aquatic life, crucial for maintaining the health of these ecosystems. Fish species, a key component of local subsistence diets, are particularly affected, with populations dwindling as their habitats degrade.

Broader Implications for Local Communities

The implications of these environmental changes extend beyond ecology. For rural communities in Alaska, which rely heavily on subsistence fishing and natural water sources, the degradation of stream quality poses a direct threat to food security and water safety. The research emphasizes the need for ongoing monitoring and intervention to mitigate these impacts and protect community health and livelihoods.

Conceptual models of hypothesized processes contributing to the discoloration of Arctic streams in Alaska’s Brooks Range. The illustration includes consequences for water quality, aquatic food webs, and human implications, including drinking water and subsistence fishing.

Urgent Measures Required

The discoloration of Arctic streams serves as a visible indicator of deeper environmental disturbances linked to climate change. This situation calls for urgent research and adaptive management strategies to address the impacts of permafrost thaw. It highlights the necessity for increased monitoring to track the progression of these changes and for developing strategies to mitigate their adverse effects on Arctic waterways and the communities that depend on them.

Summing Up

The rusting of Arctic streams is more than an environmental curiosity; it is a clarion call highlighting the urgent need for action in the face of climate change. As permafrost continues to thaw, understanding its impact on Arctic hydrology and biogeochemistry becomes crucial. This study lays the groundwork for further research and action, aiming to preserve the Arctic’s ecological integrity and ensure the health and safety of its inhabitants.

Understanding PFAS: A Look at the Awareness and Impact on U.S. Drinking Water

November 25, 2023 / activist360

The presence of per- and polyfluoroalkyl substances (PFAS) in U.S. drinking water has emerged as a critical environmental and public health issue. Despite increasing media coverage and governmental attention, a significant gap exists in the general public’s understanding of PFAS. An exploratory study by Texas A&M AgriLife scientists and published in PLoS ONE, aimed to bridge this gap by assessing public awareness regarding PFAS and their potential impact on community health and drinking water.

Key Findings of the Nationwide Survey

Limited Public Awareness: Alarmingly, nearly half of the respondents (45.1%) were unfamiliar with PFAS. Additionally, 31.6% had heard of PFAS but lacked an understanding of what it entails.
Perception of Drinking Water Safety: A striking 97.4% did not believe their drinking water was affected by PFAS, indicating a disconnect between public perception and environmental realities.
Community Exposure as a Predictor: Awareness due to known community exposure emerged as the strongest predictor of PFAS awareness. Those aware of community exposure were more informed about PFAS sources and likely to change their product usage habits.

PFAS: An Overview

PFAS, often termed “forever chemicals” due to their persistence in the environment and in our bodies, are resistant to water, grease, and heat and found in a range of everyday products including food packaging, clothing, cosmetics, and toilet paper. PFAS have been widely used in various industrial processes and consumer products since the 1940s. Their presence in products ranging from non-stick cookware to fire extinguishing foams raises significant environmental concerns, particularly in water sources. The resistance of PFAS to degradation leads to bioaccumulation, posing serious health risks such as cancer, hormone disruption, liver damage, weakened immune systems, and reproductive harm.

Regulatory Response and Public Health Implications

The U.S. Environmental Protection Agency (EPA) has recently proposed stricter regulations to limit PFAS in drinking water, reducing the maximum contaminant levels from 70 parts per trillion (ppt) to 4 ppt. This move, coupled with significant financial settlements from major corporations for PFAS clean-up, highlights the urgency of addressing PFAS contamination. However, the public’s limited awareness and understanding hinder effective response and mitigation efforts.

The Gap in Public Perception and Knowledge

The importance of knowing about PFAS lies in the need to understand the potential health risks associated with exposure to these substances. The general public’s awareness and knowledge of PFAS have been found to be limited, with only about half of the respondents in a nationwide survey stating they were aware of PFAS as an environmental contaminant. This study underscores a critical gap in public awareness and understanding of PFAS. This lack of awareness extends to the potential contamination of their primary drinking water sources.

Community exposure was identified as the strongest predicting factor regarding the level of public knowledge and awareness of PFAS and its sources. Therefore, it is crucial to provide accurate, real-time data on PFAS exposure to empower consumers to make informed decisions and take necessary precautions. Additionally, clear labeling of PFAS products is essential to allow consumers to be aware of their exposure frequency and make adjustments in product use as desired.

The Role of Effective Communication

Government agencies, research organizations, universities, utilities, and scientific institutions must collaborate to provide clear, accessible, and actionable information about PFAS, their sources, and health implications. This effort should aim to make the information relevant and understandable to the general public, encouraging informed decision-making and behavioral changes to reduce PFAS exposure. Manufacturers should clearly label their products with the presence of PFAS. This transparency allows consumers to be aware of their exposure frequency and make adjustments in product use. Consumers may want to install point-of-use treatment devices, such as under-sink or countertop filters, in their homes to remove PFAS from drinking water. These devices often use activated carbon or reverse osmosis technology to effectively reduce PFAS levels.

Source: Berthold TA, McCrary A, deVilleneuve S, Schramm M (2023) Let’s talk about PFAS: Inconsistent public awareness about PFAS and its sources in the United States. PLoS ONE 18(11): e0294134.

Light pollution is disrupting the seasonal rhythms of plants and trees, lengthening pollen season in US cities

July 17, 2022 / activist360

By Yuyu Zhou, The Conversation (CC BY-NC-ND 4.0).

The big idea

City lights that blaze all night are profoundly disrupting urban plants’ phenology – shifting when their buds open in the spring and when their leaves change colors and drop in the fall. New research I co-authored shows how nighttime lights are lengthening the growing season in cities, which can affect everything from allergies to local economies.

In our study, my colleagues and I analyzed trees and shrubs at about 3,000 sites in U.S. cities to see how they responded under different lighting conditions over a five-year period. Plants use the natural day-night cycle as a signal of seasonal change along with temperature.

We found that artificial light alone advanced the date that leaf buds broke in the spring by an average of about nine days compared to sites without nighttime lights. The timing of the fall color change in leaves was more complex, but the leaf change was still delayed on average by nearly six days across the lower 48 states. In general, we found that the more intense the light was, the greater the difference.

Chart: The Conversation/CC-BY-ND Source: Meng, et al. 2022 Get the data Download image

We also projected the future influence of nighttime lights for five U.S. cities – Minneapolis, Chicago, Washington, Atlanta and Houston – based on different scenarios for future global warming and up to a 1% annual increase in nighttime light intensity. We found that increasing nighttime light would likely continue to shift the start of the season earlier, though its influence on the fall color change timing was more complex.

Why it matters

This kind of shift in plants’ biological clocks has important implications for the economic, climate, health and ecological services that urban plants provide.

On the positive side, longer growing seasons could allow urban farms to be active over longer periods of time. Plants could also provide shade to cool neighborhoods earlier in spring and later in fall as global temperatures rise.

But changes to the growing season could also increase plants’ vulnerability to spring frost damage. And it can create a mismatch with the timing of other organisms, such as pollinators, that some urban plants rely on.

*Urban light intensity varies among cities, and among neighborhoods within cities. Yuyu Zhou, CC BY-ND*

A longer active season for urban plants also suggests an earlier and longer pollen season, which can exacerbate asthma and other breathing problems. A study in Maryland found a 17% increase in hospitalizations for asthma in years when plants bloomed very early.

What still isn’t known

How the fall color timing will change going forward as night lighting increases and temperatures rise is less clear. Temperature and artificial light together influence the fall color in a complex way, and our projections suggested that the delay of coloring date due to climate warming might stop midcentury and possibly reverse because of artificial light. This will require more research.

How urban artificial light will change in the future also remains to be seen.

One study found that urban light at night had increased by about 1.8% per year worldwide from 2012-2016. However, many cities and states are trying to reduce light pollution, including requiring shields to control where the light goes and shifting to LED street lights, which use less energy and have less of an effect on plants than traditional streetlights with longer wavelengths.

Urban plants’ phenology may also be influenced by other factors, such as carbon dioxide and soil moisture. Additionally, the faster increase of temperature at night compared to the daytime could lead to different day-night temperature patterns, which might affect plant phenology in complex ways.

Understanding these interactions between plants and artificial light and temperature will help scientists predict changes in plant processes under a changing climate. Cities are already serving as natural laboratories.