Alaska's rivers are turning bright orange and as acidic as vinegar as toxic metal escapes from melting permafrost

[Admin]

Alaska's melting permafrost is dumping toxic metals into the state's rivers, turning them bright orange and making the water highly acidic. The contaminated rivers are so vibrant they can be seen from space, and the problem is likely to get much worse in the future.

Alaska's rivers are turning bright orange and as acidic as vinegar as toxic metal escapes from melting permafrost : Read more

 

[Meteoric Marmot]

It's nice to know that the world will be a more colourful place thanks to climate change. Too bad about the fish...

/s

 

[Unclear Engineer]

This story is not making sense to me.

Where did the metal ion "contamination" in the thawing permafrost come from to be in that permafrost in the first place? Considering how long it has been frozen, it seems unlikely that this contamination was cause by human activities - unless some sort of mining is trying to inject waste liquids under the permafrost. But, if that were the case, I would expect the article to use it to blame humans even more. The article says it came from "the rocks", so it sounds like natural ore deposits.

So, how about an explanation for why there is so much metallic content in permafrost that it can turn the water orange?

The pH seems about right for pure tannic acid. Tannic acid typically results from decay of vegetation. Usually, it is more diluted and turns water brownish. Rivers and swamps in the south have "black water" due to that. Many species of fish live in them.

So, how about the rest of the story? Are there dead fish floating down these rivers? Do sediment cores taken off the north coast of Alaska show any previous episodes of these same chemicals, for instance at about 120,00 years ago, during the previous interglacial warm period?

 

[Helio]

So, how about an explanation for why there is so much metallic content in permafrost that it can turn the water orange?

Yeah, there are some important questions to ask.

Here is the Nature article on it. It looks like the bulk of it is found in sulfides, especially iron sulfides.
There is an interesting ground picture showing the color change in one year, but I notice that the deeper background water is blue, which I'm unclear what this suggests.

The Nature article mentions that there is little research as to why those minerals are there in the first place, likely not due to prior mining.

The fish count reduction before and after seems to be only in this section of the stream. Are they more abundant in what I think is the deeper water?

No doubt this is a problem that would be great to solve and counteract its effects, if possible.

 

[Unclear Engineer]

If this produces a discovery of large deposits of important metal ores, it might result in mining - and that would really have a high probability of messing up the local environment. The area north of the Brooks Range in Alaska is really "remote" and, so far, not badly damaged by human activities.

 

[Unclear Engineer]

Helio, Thanks for the link.

It does make the problem sound somewhat less serious, at least at its present level.

For instance, the samples of the impaired streams' pH seems to be much better than the 2.3 stated in the Space.com article, and that low value seems to be for seeps before dilution in a stream. For streams, the Nature article says:
"In our study, orange streams had lower pH (mean pH ± standard deviation = 7.41 ± 0.75) compared to reference streams (7.98 ± 0.24; two-tailed t test: t = 2.510, df = 20, P = 0.035;" and it says most of the metals were in particulates. This indicates that there is substantial buffering in the natural streams, which is what I would expect.

It would be helpful if there was some indication of what fraction of streams in the area are severely yellowed. The Nature article talks about comparing the yellowed streams to "nearby streams" that are not affected. So, although the effect is observed over a very long distance along the backbone of the Brooks Range, it is not clear that it (currently?) affects a large fraction of the numerous streams in that region.

It would also help to know if the yellowing is transient, or constant or increasing in the affected streams. If this is the new normal for all streams, then it is definitely a big deal. If it only affects a small fraction of all streams, then it might not be such a big deal. If it is a relatively short term effect when some particular depth of the permafrost thaws and accumulated weathering materials are flushed out with increased water flow-through, then it might not be such a bid deal.

It definitely warrants further study. But, we need to understand that we aren't going to reverse this effect in the foreseeable future by lowering CO2 emissions. We are going to have to live with / adapt to whatever this becomes.

 

[The_Guchi]

I'm wondering how the author came to the conclusion that this was caused by human influenced climate change versus because of the fact that we are in a warming phase at the tail end of an ice age???

 

[Unclear Engineer]

That is why I asked if there are any well cores that show stratigraphy going back several ice ages, taken from places which could tell us if this has happened before.

 

[COLGeek]

I'm wondering how the author came to the conclusion that this was caused by human influenced climate change versus because of the fact that we are in a warming phase at the tail end of an ice age???

This is not an either/or topic. But both. While there are natural climate cycles, human activity exacerbates those cycles. That is a significant part of what many miss in discussing these issues.

This is based on science, not political ideologies or conspiracy theories.

 

[Unclear Engineer]

This is not an either/or topic. But both. While there are natural climate cycles, human activity exacerbates those cycles. That is a significant part of what many miss in discussing these issues.

This is based on science, not political ideologies or conspiracy theories.

I am going to disagree with that to some degree. The article unequivocally says it is the result of "human-caused climate change."

Yes, we are doing "science" to study the phenomenon, and it seems clear that the thawing tundra is causing the "yellowing" phenomenon in some streams. And, it is clear that the climate there and pretty much everywhere else on Earth is warming.

We even know that adding CO2 to the atmosphere increases Earth's surface temperatures. Not to mention the methane and other compounds we emit from our industries.

But, we also know that the Earth's climate has been going through freeze-thaw cycles for the last 3 million years, first on a frequency of about 50,000 years, but changing to a frequency of about 100,000 years about 900,000 years ago.

We do have the "science" to recognize astronomical influences on Earth's climate, and we do have the "science" to read the geological records about past climate values, including sea levels, temperatures and CO2 concentrations.

But, at this point in our scientific understanding, we do not have computer models of the Earth's climate that can replicate the past ice ages and warm periods. We can tell that there are some effects that we cannot model accurately enough, and those seem to involve circulation patterns of air and water, and maybe some chemicals.

So, were really are not able to "scientifically" say exactly what the Earth's climate would be like today if humans had not affected it, nor what it would have done before starting the next ice age (which we may or may not have stopped). We do have some hints that sea level eventually got substantially higher in previous warm periods than it is today (e.g., about 25' higher 120,00 years ago than now). So, it is not a safe bet that the planet would be naturally cooling off, now, without human effects.

And, expecting the climate to remain static is definitely not "scientific". We have plenty of evidence that it changes dramatically over periods of 10,000 to 100,000 years, with some pretty big and rapid changes at some points in cycles. Sea level was about 325' lower than it is today, about 25,000 years ago.

So, getting back to the yellowing streams, the "scientific" question to ask is whether this also has happened in previous interglacial warm periods, or is it "unprecedented" in those natural cycles.

And, I suggest that looking for indications of previous occurrences in cores of sediments extracted from local wells would help address that question. I expect that some of the exploratory drilling done around Prudhoe Bay might be useful to address that question.

 

[COLGeek]

I am going to disagree with that to some degree. The article unequivocally says it is the result of "human-caused climate change."

Yes, we are doing "science" to study the phenomenon, and it seems clear that the thawing tundra is causing the "yellowing" phenomenon in some streams. And, it is clear that the climate there and pretty much everywhere else on Earth is warming.

We even know that adding CO2 to the atmosphere increases Earth's surface temperatures. Not to mention the methane and other compounds we emit from our industries.

But, we also know that the Earth's climate has been going through freeze-thaw cycles for the last 3 million years, first on a frequency of about 50,000 years, but changing to a frequency of about 100,000 years about 900,000 years ago.

We do have the "science" to recognize astronomical influences on Earth's climate, and we do have the "science" to read the geological records about past climate values, including sea levels, temperatures and CO2 concentrations.

But, at this point in our scientific understanding, we do not have computer models of the Earth's climate that can replicate the past ice ages and warm periods. We can tell that there are some effects that we cannot model accurately enough, and those seem to involve circulation patterns of air and water, and maybe some chemicals.

So, were really are not able to "scientifically" say exactly what the Earth's climate would be like today if humans had not affected it, nor what it would have done before starting the next ice age (which we may or may not have stopped). We do have some hints that sea level eventually got substantially higher in previous warm periods than it is today (e.g., about 25' higher 120,00 years ago than now). So, it is not a safe bet that the planet would be naturally cooling off, now, without human effects.

And, expecting the climate to remain static is definitely not "scientific". We have plenty of evidence that it changes dramatically over periods of 10,000 to 100,000 years, with some pretty big and rapid changes at some points in cycles. Sea level was about 325' lower than it is today, about 25,000 years ago.

So, getting back to the yellowing streams, the "scientific" question to ask is whether this also has happened in previous interglacial warm periods, or is it "unprecedented" in those natural cycles.

And, I suggest that looking for indications of previous occurrences in cores of sediments extracted from local wells would help address that question. I expect that some of the exploratory drilling done around Prudhoe Bay might be useful to address that question.

So, long story short, not an either/or issue as previously (concisely) stated.

Of course it is a complex issue, but to assume that human activity has no impact on the climate is wrong.

 

[Helio]

There is an earlier (Jan. 2024) related story I found interesting in Sc. Am. here.

It seems to say both bacterial processes and acidic leeching seem to be at work in the thawing permafrost.

"New groundwater flows have developed in the thawing earth, Cooper said, and they have “really awakened a lot of these geochemical processes that have been basically stalled out for 5,000 years because the ground's been frozen.”

It seems that global warming, not direct anthropogenic involvement, at least, is to blame. I think this is consistent with this onsite article.

Ironical, in the latter paragraphs, the discoloring of one of the rivers in the past brought in a mining operation. This operation improved river conditions. It may be now closed due to environmental requirements placed on it.

 

[Unclear Engineer]

Trying not to be argumentative, but the post was

I'm wondering how the author came to the conclusion that this was caused by human influenced climate change versus because of the fact that we are in a warming phase at the tail end of an ice age???

And, that seems to have been based on the part of the article that says:

"As the frozen ground thaws thanks to human-caused climate change, . . ."

That sure seems to imply to a reader that it would not have happened if it had not been for "human-caused climate change".

So, while we agree on you point that it's "not an either/or issue", the question was how the author of the article seemed to make it a "human caused" issue. If you think it is improper to say it clearly was not caused by humans, then don't you think it is improper to imply that it clearly is caused by humans? And, even if it is caused earlier than normal by humans, that is different from it not happening at all if it had not been for humans.

So, I am going to go with The_Guchi and call the article statement questionable, and politically biased.

 

[COLGeek]

So, I am going to go with The_Guchi and call the article statement questionable, and politically biased.

The actual study (linked in article) doesn't directly say "human caused". An interesting read.

 

[Helio]

I personally find it admirable when science articles attribute global warming effects to global warming effects, respecting the uncertainty found in humankind's percent contribution. [Apparently, the first two IPCC assessments did this.]

Climate modeling is improving and perhaps it will someday make testable, accurate predictions and retrodictions. More variables have been recently added to the modeling. IIRC, volcanic activity was one.

 

[Unclear Engineer]

Helio, Thanks for the second link.

That shows the problem to be pretty wide-spread in the individual rivers impacted, not just a matter for small feeder streams.

Some things that struck me about the article were:

1. The mine at Red Dog was founded on the basis of having seen this type of drainage in the 1960s, so that is pretty early in the human-induced global warming scenario.
2, The article talks about the underlying processes having been inhibited by being frozen for "5,000 years". I would think it has been frozen for a lot longer than that, maybe 50,000 years? I wonder if that was a typo.

The article says " Perhaps the only real hope is that once all the permafrost has thawed and all the iron has rusted, these wild rivers will be able to flush out the contamination and restore themselves, although that would take decades at least."

If this has happened in the past, and these streams and rivers did flush out and restore water quality without refreezing the tundra, that would be good to know. Again, sediment cores taken in the rivers' mouths might be able to show if this has happened before, and approximately when and how long it lasted.

 

[SPHYNX99752]

This story is misleading at best. Geological changes happen all the time.