//
you're reading...

Chemistry

Fresh(water) (P)Rinse of (not)Bel Air: The Decreasing Salinity of the Japan Sea

References: Kosugi, Naohiro; Hirose, Nariaki; Toyoda, Takahiro; Ishii, Masao. (2021). Rapid freshening of Japan Sea Intermediate Water in the 2010s. J. Oceanogr. 77, 269-281.

DOI: https://doi.org/10.1007/s10872-020-00570-6

Reading Time: 5 minutes

Picture your average rainy day. The grey clouds, the pattering of rain outside, the humidity in the air. When all of that rain falls, where does it go? From when we are children, we are taught that water flows downward with gravity. Given the dynamic shape of the land around us, where water flows becomes a more difficult question. Water drains depending on your local watershed, which are areas of land that people have mapped where water flows. For example, rain may flow from your backyard into a local creek, which dumps off into the closest river, which can make it all the way out to the ocean. With these kind of complex dynamics, it can be hard to understand how our water sink (the final destination of flowing water) is affected by its source (the source of flowing water like rain or farms). Furthermore if our source is fresh water (like rain) and our sink is salt water (like the ocean), what happens when they are mixed?

A map of the Sea of Japan, the site of this scientific study. Image Credit: History Maps

A team of scientists from the Meteorological Research Institute in Tsukuba-shi of the Ibaraki prefecture in Japan decided to investigate this question. The group analyzed the mixture of large influxes of fresh water into the Japan Sea. Specifically they focused on the Japan Sea Intermediate Water (JSIW), which is near a depth of ~500m, during the 2010s decade. The intermediate water of most oceans are sensitive to changes in the climate, ocean circulation (aka the ocean conveyor belt), and local water influx from nearby watersheds. The team measured the salinity of the JSIW across multiple seasons and years to examine its properties as time passed. Today, we are going to see what they found out.

What did they find?

The group found that the JSIW is freshening (decreasing in salinity) at a very quick pace! While the intermediate water of oceans are freshening at their own rate, the JSIW is double that! The group spent a lot of time deducing why the JSIW was freshening faster than the other oceans. By performing a lot of calculations, they could decipher what sources of water (like rivers and land runoff) influenced the JSIW the most. The team calculated that the JSIW (the sink for this study) was influenced by an influx of water from the East China Sea and a large amount of rain during the decade (the sources). These results indicate that the Japan Sea is very sensitive to its local environment and weather.

How did they do it?

 

A rainy day in Tokyo. Precipitation can highly influence the salinity of the Japan sea. Image Credit: Dane Siestas

The team used a plethora of sources to form these conclusions. They manually performed measurements of salinities (as well as other molecules important to measure like oxygen and phosphate) on ships, they utilized measurements of precipitation (like rain) from the Japanese 55-year reanalysis dataset (JRA-55), they used the FORA-WNP30 data set to study ocean water flow, and they employed data from the National Oceanographic Data Center to double check some of their values. Last, the team collected data about the salinity and flow of the Changjiang River from the Ministry of Water Resources of China to analyze its impact on the salinity of the JSIW. All of these resources helped the group analyze the JSIW as well as deduce what caused the results they found. After some mathematical modelling, the group could conclude how the sources of water affected the sink of the JSIW.

Why does it matter?

This investigation tells us a lot about the environmental sensitivity of our oceans, especially smaller ones like the Japan Sea. The properties of these waters determine several important aspects of marine life for both animals and humans living on the coast. So, it is extremely important to understand how the waters change over time! With this knowledge, we can better how our oceans respond to our changing climate in the future as well as predict how marine life will change in response.

Discussion

No comments yet.

Post a Comment

Instagram

  • by oceanbites 2 weeks ago
    Happy Earth Day! Take some time today to do something for the planet and appreciate the ocean, which covers 71% of the Earth’s surface.  #EarthDay   #OceanAppreciation   #Oceanbites   #CoastalVibes   #CoastalRI 
  • by oceanbites 1 month ago
    Not all outdoor science is fieldwork. Some of the best days in the lab can be setting up experiments, especially when you get to do it outdoors. It’s an exciting mix of problem solving, precision, preparation, and teamwork. Here is
  • by oceanbites 2 months ago
    Being on a research cruise is a unique experience with the open water, 12-hour working shifts, and close quarters, but there are some familiar practices too. Here Diana is filtering seawater to gather chlorophyll for analysis, the same process on
  • by oceanbites 3 months ago
    This week for  #WriterWednesday  on  #oceanbites  we are featuring Hannah Collins  @hannahh_irene  Hannah works with marine suspension feeding bivalves and microplastics, investigating whether ingesting microplastics causes changes to the gut microbial community or gut tissues. She hopes to keep working
  • by oceanbites 4 months ago
    Leveling up - did you know that crabs have a larval phase? These are both porcelain crabs, but the one on the right is the earlier stage. It’s massive spine makes it both difficult to eat and quite conspicuous in
  • by oceanbites 4 months ago
    This week for  #WriterWednesday  on  #Oceanbites  we are featuring Cierra Braga. Cierra works ultraviolet c (UVC) to discover how this light can be used to combat biofouling, or the growth of living things, on the hulls of ships. Here, you
  • by oceanbites 4 months ago
    This week for  #WriterWednesday  at  #Oceanbites  we are featuring Elena Gadoutsis  @haysailor  These photos feature her “favorite marine research so far: From surveying tropical coral reefs, photographing dolphins and whales, and growing my own algae to expose it to different
  • by oceanbites 5 months ago
    This week for  #WriterWednesday  on Oceanbites we are featuring Eliza Oldach. According to Ellie, “I study coastal communities, and try to understand the policies and decisions and interactions and adaptations that communities use to navigate an ever-changing world. Most of
  • by oceanbites 5 months ago
    This week for  #WriterWednesday  at  #Oceanbites  we are featuring Jiwoon Park with a little photographic help from Ryan Tabata at the University of Hawaii. When asked about her research, Jiwoon wrote “Just like we need vitamins and minerals to stay
  • by oceanbites 5 months ago
    This week for  #WriterWednesday  on  #Oceanbites  we are featuring  @riley_henning  According to Riley, ”I am interested in studying small things that make a big impact in the ocean. Right now for my master's research at the University of San Diego,
  • by oceanbites 5 months ago
    This week for  #WriterWednesday  at  #Oceanbites  we are featuring Gabby Stedman. Gabby is interested in interested in understanding how many species of small-bodied animals there are in the deep-sea and where they live so we can better protect them from
  • by oceanbites 6 months ago
    This week for  #WriterWednesday  at  #Oceanbites  we are featuring Shawn Wang! Shawn is “an oceanographer that studies ocean conditions of the past. I use everything from microfossils to complex computer models to understand how climate has changed in the past
  • by oceanbites 6 months ago
    Today we are highlighting some of our awesome new authors for  #WriterWednesday  Today we have Daniel Speer! He says, “I am driven to investigate the interface of biology, chemistry, and physics, asking questions about how organisms or biological systems respond
  • by oceanbites 7 months ago
    Here at Oceanbites we love long-term datasets. So much happens in the ocean that sometimes it can be hard to tell if a trend is a part of a natural cycle or actually an anomaly, but as we gather more
  • by oceanbites 7 months ago
    Have you ever seen a lobster molt? Because lobsters have exoskeletons, every time they grow they have to climb out of their old shell, leaving them soft and vulnerable for a few days until their new shell hardens. Young, small
  • by oceanbites 8 months ago
    A lot of zooplankton are translucent, making it much easier to hide from predators. This juvenile mantis shrimp was almost impossible to spot floating in the water, but under a dissecting scope it’s features really come into view. See the
  • by oceanbites 8 months ago
    This is a clump of Dead Man’s Fingers, scientific name Codium fragile. It’s native to the Pacific Ocean and is invasive where I found it on the east coast of the US. It’s a bit velvety, and the coolest thing
  • by oceanbites 9 months ago
    You’ve probably heard of jellyfish, but have you heard of salps? These gelatinous sea creatures band together to form long chains, but they can also fall apart and will wash up onshore like tiny gemstones that squish. Have you seen
  • by oceanbites 9 months ago
    Check out what’s happening on a cool summer research cruise! On the  #neslter  summer transect cruise, we deployed a tow sled called the In Situ Icthyoplankton Imaging System. This can take pictures of gelatinous zooplankton (like jellyfish) that would be
  • by oceanbites 10 months ago
    Did you know horseshoe crabs have more than just two eyes? In these juveniles you can see another set in the middle of the shell. Check out our website to learn about some awesome horseshoe crab research.  #oceanbites   #plankton   #horseshoecrabs 
WP2Social Auto Publish Powered By : XYZScripts.com