2020年7月30日木曜日

原発は海を温める!?_その2 Nuclear power warms the sea !?_No. 2 2020-07 #2

 先回の新聞記事を紹介した後、その付近の海域の海水面の温度上昇も確認してみた。以前から日本海中部の温度上昇が際立って高い事は気になっていたので、偶々5年前に地球温暖化問題について調べた時の図と見比べてみた。
 上が今年(2020年)、下が2015年のものである。
 どちらも他の海域よりも日本海中部の温度上昇の幅が大きいが、見比べてみて「おやっ?」と思う事がある。他の海域はどこも5年間で温度上昇の幅が大きくなっているのに日本海中部は増えていないのである。
 そこで、日本海中部の温度変化を取り出してみた(一番下の図)。
 他の海域の温度が2010年以降も上がり続けているのに、この海域だけ2011年から下降傾向である。
 この点については次回に詳しく検討したい。

 今回示す図はどれも気象庁の下記のサイトで見る事が出来る。興味のある人は他の海域の温度変化のパターンも見られるとよいだろう。

 After the author introduced the newspaper article in the last issue, I also checked the sea surface temperature rise in the area around the bay. Since I have been concerned about the conspicuously high temperature rise in the central Japan Sea for some time, I compared it with a chart I did a study on global warming five years ago.

 The top one is for this year (2020) and the bottom one is for 2015.

 In both cases, the range of temperature rise in the central Japan Sea is larger than in other areas of the ocean, but I found myself saying, "Wow!" when I compared them. I have a feeling that this is not the case in the central Japan Sea. While the range of temperature increase has been increasing over the past five years in all other areas around Japan, there has been no increase in the central Japan Sea.

 Then, I took out the temperature change in the central Japan Sea (bottom figure).

 The temperature in the central Japan Sea is on a downward trend since 2011, while the temperature in other areas of the ocean has been increasing since 2010.

 The author will discuss this point in more detail in the next issue.

 All of the charts shown here can be found on the Japan Meteorological Agency's website below. If you are interested in these charts, you may want to look at the patterns of temperature changes in other areas of the ocean. 

Translated with www.DeepL.com/Translator (free version)

Some small errors were corrected after translation with DeepL.





2020年7月29日水曜日

原発は海を温める!?_その1 Nuclear power warms the sea !?_No. 1 2020-07 #1

 1年以上ブログの更新をさぼって来たが、下記の記事をきっかけに海の温暖化の話から再開し、地球温暖化の問題について8月下旬まで集中して書いていきたいと思います。
 記事は6月30日付の福井新聞の記事で、原発稼働中周辺の海水温が2℃高くなっていた、と書いてある。一番下に原発周辺の地図を載せた。この調査が若狭湾内のどの辺りで実施されたかは分からないが、かなり広い水域で2℃海水温が上昇するのは大変な事である。

 文中に石炭火力発電所の近くでは原発近くのような変化は見られなかったとあるが、原発では排熱(元の熱量の2/3)が全て海に放出されるのに比べ、石炭火力の場合煙突からの熱の放出もかなりの量になり、海への影響が小さいためであると考えられる。

 I have been skipping blog posts for more than a year, but the following article has inspired me to resume writing about oceanic warming and to concentrate on the issue of global warming until late August.
 The article is from the Fukui Shimbun dated 30th June and it says that the sea water temperature around the plant was 2°C higher during the operation. At the bottom of the page is a map of the area around the plant. We don't know where in Wakasa Bay this survey was carried out, but it's amazing that the sea water temperature rose 2°C in a fairly large area of water.

   The text states that no change was observed near coal power plants as compared to near nuclear power plants. This is thought to be because, compared to nuclear power plants where all the waste heat (2/3 of the original heat) is released into the sea, coal-fired power plants also release a significant amount of heat from their stacks, which has a smaller impact on the sea.


English translation of above article is following.

Tropical fish have settled in the Sea of Japan due to the effluent of nuclear power plants

The area around the Takahama nuclear power plant, the fish disappeared after shutdown of the plant

  Tropical fish had become established in the vicinity as the sea was warmed by effluent from the Kansai Electric Power Co.'s Takahama nuclear power plant in Fukui Prefecture, Prof. Reiji Masuda of Kyoto University's Maizuru Fisheries Laboratory published the results of his research in the online scientific journal PLOS ONE by June 29. Juvenile fish brought in from the south by ocean currents are thought to have successfully overwintered, but they disappeared when the plant was shut down after the Great East Japan Earthquake.

  During the operation of the nuclear power plant, the seawater temperature around the plant was 2°C higher, which is equivalent to conditions around 2050 when global warming has advanced. Mr. Masuda said, "It's not a good thing that the habitat has expanded. If a lot of nuclear power plants operate in the narrow Sea of Japan, the environment will change drastically, including a decrease in fish and seaweed that originally existed," he said. He called attention to the effects of localised global warming caused by the thermal discharge of nuclear power plants.

  From 2004 to 2005, Mr. Masuda conducted a diving survey in the sea near the Takahama Nuclear Power Plant in Wakasa Bay during the winter. During the operation of the plant, the discharge of water at the site was seven degrees Celsius warmer than normal, which increased the number and variety of fish, and tropical fish, such as the Atlantic wrasse and the thunderhead wrasse, which normally cannot overwinter, were also found in the water.

 When the Takahama nuclear power plant was shut down in 2012, the water temperature dropped and returned to normal, and tropical fish died out or were no longer seen.

 For comparison, the same bay was also examined near a coal-fired power plant and in waters without waste heat facilities, but no such change was found near the plant.

Translated with www.DeepL.com/Translator (free version)

Some small errors after translation with DeepL were corrected by the author.


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