Particulate
air pollution, such as aerosols (defined as a suspension of fine solid
or liquid particles in gas),
from industries reduces the amount of sunlight that can
reach the earth’s surface. The lack of appropriate sunlight on the earth’s
surface will lead to lower temperature; consequently, there will be lower river
water evaporation and increasing water yield. Therefore, an elevated river flow
will be observed.
The ScienceDaily
article Air Pollution Increases River Flows summarizes a
recently published Nature Geoscience journal article, Detection of Solar Dimming and Brightening
Effects on Northern Hemisphere River Flow, which shows that serious air
pollution has led to increased river flows.
Credit: Fyle/Fotolia
The ScienceDaily article claims “air pollution has had a significant impact on the amount of
water flowing through many rivers in the northern hemisphere”. Because of the
increasing amount of air pollution, more and more sunlight is reflective so
that they cannot reach the earth surface, which can refer to a new term “solar
dimming”. As a result, an increasing in river flows is observed. Not only did
they notice increasing air pollution leading to increasing river flows,
but also the reverse way. “When the dimming began to reverse, reductions in
river-flows were observed”. The key point in this article is discussing the relationship
between the air pollution and flow rate. The ScienceDaily author states that the
research group did take temperature and other aspects into consideration.
The Nature Geoscience article provides more detailed
information regarding the model (a global land surface model: JULES) and methods
they used to do the comparison. In addition, carbon dioxide and landuse were also
considered to compare and contrast their effects on river flows.
Overall, I think the ScienceDaily article did a good job
summering the main points of the Nature Geoscience article in an easy
understanding way. It requires a lot of background knowledge to read the Nature
Geoscience article since probably many audiences do not know the methods they
used. Additionally, the ScienceDaily article gives explanations to professional
terms, like “solar dimming”. As for the shortcomings of the article, I think it
would be better if a little more detailed information were provided. From my
point of view, I would give this article 8.5/10.
ScienceDaily article
Nature Geoscience article (you will need to log into MLibrary)
We usually hear about rising sea levels due to the increase in temperature leading to melting polar ice, but I had not heard of increasing river flows. Are there the same concerns with rising river levels as rising sea levels (ex. additional flooding, loss of land, etc.?)
ReplyDeleteThey might lead to the same result, but the paths are different, I think. In the Nature GeoScience article, they "formally detect and quantify the historical effect of changing aerosol concentrations, via solar radiation, on observed river flows". So I think they are trying to link air pollution and river flows directly.
DeleteIt would be interesting to see if these predictions can be seen in records of stream flow. I could see how this effect might get lost in other impacts of climate change.
ReplyDeleteI appreciate that the authors accounted for variance in other factors leading to river flow rate, such as temperature, CO2 and land use, but I feel like there may be more factors at play than just lesser evaporation of the surface water. It would be interesting to see how this affects river patterns in the future, and how this excess river flow might be used to our benefit!
ReplyDeleteI think the Science Daily article did a good job of explaining the importance of air pollution. Is an increase in river flows a positive or negative impact though? I found it interesting that neither Science Daily nor Nature Geoscience mentioned the words “positive” or “negative.” Does an increase in river flow benefit aquatic organisms? What are some of the negative implications of increased river flow other than affecting the morphology of rivers? I liked how Science Daily brought up the term “solar dimming,” I have not previously heard of this term before but it is very interesting. Nature Geoscience states that in 1980, an increase in river flow of up to 25% occurred when aerosol levels were at their peak. This is just an estimation based on modeling, I wonder if future experiments will be conducted to find current exact measurements on rising river flow.
ReplyDeleteI agree. Theses predictions would probably hold more weight and receive more attention if the potential impacts (both positive and negative) of increased river flows are further studied and revealed.
DeleteIt's interesting to see how in in some areas of the world, rising river levels and currents are being observed while in other parts, riverbeds and lakes are being dried up. Curious to see how these two phenomena are intertwined.
ReplyDelete