Qilin Li
Professor Joel Wood
WR 39C 33354
January 24, 2022
I felt good about my revision here for I have added many relevant data and raised many why important questions like water quality is important because it can also affect the drinking water quality. I also incorporated many new sources of evidence from scholarly articles to enhance the previous arguments. Yet as professor Wood points out, there are grammar errors as a result.
Climate change and water quality
People nowadays are generally more aware of climate change and its influential effects on earth, worldwide rivers, oceans are part of the victim of this human-incurred change as well. Yet how many of us would really dig a little further to look at how they are influenced? Take Rhine and Meuse rivers in a low-lying Netherland near the delta for example. In year 2003, after six months of drought, the water discharge is significantly lower than that in 2002. The water flow was 778 m3/s compared to 1385 m3/s in 2002. Rhine rivers gather its flow primarily through the snowmelt from the Alps and Meuse solely depends on rainfall and thus only amount to 20 m3/s in median discharge.
This long period of drought has certainly a major impact on water quality resulted from aspects like temperature, oxygen dissolved and the chloride concentrations. All three of them are interconnected, when there is an increase in river temperature, dissolved oxygens in water may decline and thus more chloride concentrations. Effects derived from those potentially could be emergence of fish bodies and deteriorated underwater plants in the zone which will inevitably pollute daily drinking sources of ours. A more directly influence of climate change can be seen from a heavy rainfall (Shanley,1971). One can imagine that after a huge raining near the river, it is not just the dirt, but nutrients within it which can pollute the water body. There are many nutrients that are harmful to water (Kundzewicz,2010) like heavy metals, toxic organic pollutants and pathogens. Below are contents addressing how various conditions of climate change could alter quality of water and they are important not just in a way to preserve the precious water but to potentially deter the series of problems brought by poor water conditions.
Among above mentioned three factors influencing water quality, in a broad view, temperature is the main influencer disrupting literally all physico-chemical equilibrium and even biological reactions. More specifically stating, kinetic movement of an existing chemical reaction can increase to the extent of double as a 10 Celsius increase in temperature. As a result, Solubilization, degradation and evaporation can occur and thus further induce the increased concentration of dissolved substances and a reduction in concentrations of dissolved gases. The last point is very vital due to the fact the oxygen saturation will decrease by 10% a 3 Celsius increase in temperature. As IPCC had states, the 21-century temperature is expected to increase on average 1.8 to 4.0 degree Celsius under every scenario. It is foreseeable that soon, there would be a dying tendency in summer. People can intuitively imagine that if there are tons of fish or plant bodies in an water body, quality of the water would gradually turn bad and are not suitable of supporting its surrounding environments and animals.
Aside from that, water flow intensity is another major component which may influence water substances concentration in water as well. We would discuss this using extreme case like droughts. They alter water quality through directly dilute or concentrate the dissolved substances in the rivers. To illustrate, for low flow river, there is one obvious feature that temperature, dissolved substances in water are gradually increasing, yet the oxygen level is decreasing . Of course, there is also a positive effect which is to reduce the pollutant in water because of the low water velocity. Floods, on the other hand, could jeopardies the quality in another method. Waterborne pathogens can spread across the freshwater after a contamination by human or animal waste from heavy rainfall. When the level of flow exceeds the combined sewer system (CSS), the excess flow ran directly towards surface water. Stormwater is also one of the main sources of coliform. With above mentioned rising temperature, there is a likelihood of increased survival rate of pathogen and thus lower quality of water.
H.A.J. Selhorst gave an excellent real-life example upon above said scenarios, they choose Dutch as a subject and had studied its water systems and effluents. Many regional surface water municipal wastewater treatment plants are expected to be the main contributor of containminants. And this load of containminants will increase under low flow conditions like in summer for there is not enough water to dilute the containminants. They used statistics gathered from the basin of Dommel brook to illustrate the change. This phosphate variation given below had shown that concentration of this chemical is higher in the summertime than in the wintertime. Thus, the assumption of discharge level and containminants level correlate holds true. Therefore, there must be a continuous source of phosphate like wastewater treatment plant. And indeed, geographical distribution had shown a strong correlation between phosphate level and the presence of treatment plant. It is human intervention that directly increased the phosphate level through plant and indirectly through climate change.
All changes in water above mentioned will inevitably making a difference in human living conditions. In Delpla’s article, after introducing several basic indicators and possible influences caused by climate change upon rivers. The article later chooses to focus on a narrower yet much more relative and interesting topic which is how drinking water derived from rivers and underground water could be affected. Delpla used one historical fact from Iowa, USA to explain how floods make an impact on our daily drinking water quality. The contamination of underground water had led to the outbreak of Acanthamoeba keratitis in Iowa, 1994. Fisty percent of the water borne disease in the US during the last fifty years had followed a period of heavy rainstorm. Because floods can bring many bacteria and nutrients into the daily drinking water. And if people are drinking this kind of water, it is not hard to imagine that a large portion of the people in this town or city will get ill and even to the extent of life threatening. Although the risk related to drinking water is low in developed countries, there is a risk in private supply.
Image presented here is a summary of Delpla’s study regarding the climate change impact on surface water quality. There are two major perspectives (temperature and rainfalls) and their concrete manifestation (drought and floods). They further divide the environment into natural or man-made. For the streams, the main influencers are pathogens, cyanobacteria, and DOM (unfriendly to water). Various components which may influence water body
After carefully investigating previous research, Komatsu recognized several factors like water temperature, dissolved oxygen and nutrients from previous research and had furthered the study through a long-term investigation upon how climate change can influence water quality. They are more interested in researching the long-term effect of global warming on environmental components like water temperature and oxygen concentration. To make this clearer, they compared data in a japan reservoir to find out the difference. They simulated the results of lake model for 1991-2001 and 2091-2100 to make a comparison. And according to their study (Komatsu,2007), the surface water temperature of 2090s is 3.4 Celsius higher than the same lake from 1990s. The hypolimnion is predicted to increase by 2.8 Celsius and higher temperature might lead to longer thermal stratification period. As a result of this change, oxygen demand for aerobic decomposition and flow of phosphorus from the sediments will increase the concentration of phosphorus in the hypolimnion. Nutrients release amount change could cause the alternation in nutrient circulation. Using several models to solidify their assumption, Komatsu tested the sensitivity of lake water temperature to the climate change and the oxygen concentration inside the lake. Below is an example of annual and monthly averages of precipitations.
Fig. 5. (a) Annual averages and (b) monthly averages for measured and predicted precipitation amounts from 1981 to 2000.
In all, most of the articles recognizing there is an influence from climate change to water quality in different water body (rivers, lakes) or city drinking water. Temperature, oxygen concentration and floods are certainly major factors influencing the water quality. Many are gathering the data and comparing the difference in each time and used many models when wanting to study actual nutrients concentration in lake. These articles exemplify the severity of the influence from climate change on water quality and each carefully investigated based on former studies and had proposed several more contentions regarding this issue. Despite emphasis various from pure nutrients influence on water quality to human drinking water quality, they all set up sophisticated designs and experiments to successfully demonstrate this bigger than it appears climate change influence on water quality.
Professor Comments
Hi Qilin, Good work here! I think the steps you've taken in this draft to add extra context and interpret new information for the reader is working quite well - overall, the takeaways and applications of facts and figures feel much more relevant and impactful. As with your last draft, you've also got a lot of good, well-selected sources that help the paper feel support and driven throughout. The main area for potential improvement on this draft might be in some of its sentence mechanics and grammar. These are mostly minor (verb tense issues, missing articles), but on the whole they sometimes obscure the clarity of your thoughts and ideas in your analysis. Still, this is a strong and well constructed essay that you should be proud of! All best, - Joel
Works Cited
WHITEHEAD, P. G., et al. “A Review of the Potential Impacts of Climate Change on Surface Water Quality.” Hydrological Sciences Journal, vol. 54, no. 1, Taylor & Francis Group, 2009, pp. 101–23, https://doi.org/10.1623/hysj.54.1.101.
Delpla, I., et al. “Impacts of Climate Change on Surface Water Quality in Relation to Drinking Water Production.” Environment International, vol. 35, no. 8, Elsevier Ltd, 2009, pp. 1225–33, https://doi.org/10.1016/j.envint.2009.07.001.
Senhorst, H. A. J., and J. J. G. Zwolsman. “Climate Change and Effects on Water Quality: a First Impression.” Water Science and Technology, vol. 51, no. 5, 2005, pp. 53–59, https://doi.org/10.2166/wst.2005.0107.
Komatsu, Eiji, et al. “A Modeling Approach to Forecast the Effect of Long-Term Climate Change on Lake Water Quality.” Ecological Modelling, vol. 209, no. 2, Elsevier B.V, 2007, pp. 351–66, https://doi.org/10.1016/j.ecolmodel.2007.07.021.
Murdoch, Peter S., et al. “POTENTIAL EFFECTS OF CLIMATE CHANGE ON SURFACE‐WATER QUALITY IN NORTH AMERICA1.” Journal of the American Water Resources Association, vol. 36, no. 2, Blackwell Publishing Ltd, 2000, pp. 347–66,
https://doi.org/10.1111/j.1752-1688.2000.tb04273.x.
Shanley, Keren. “Climate Change and Water Quality: Keeping a Finger on the Pulse.” American Journal of Public Health (1971), vol. 107, no. 1, American Public Health Association, 2017, pp. e10–e10, https://doi.org/10.2105/AJPH.2016.303504.
Kundzewicz, Zbigniew W., and Valentina Krysanova. “Climate Change and Stream Water Quality in the Multi-Factor Context: An Editorial Comment.” Climatic Change, vol. 103, no. 3-4, Springer Netherlands, 2010, pp. 353–62, https://doi.org/10.1007/s10584-010-9822-9.