Climate Outcome NZ
  • Climate Outcome. Home page.
  • Latest posts & news
  • Temperature
  • Precipitation changes in a warming world.
  • Increased flood damage in a warming world.
  • Drought
  • Wind
  • El Nino Southern Ocilation. ENSO.
  • Sea Level
  • Polar melting
  • Arctic sea ice + weather.
  • West Antarctica
  • Ocean Acidity
  • Plant Die Back. Animal Migration.
  • Climate threats
  • Streams a vital resource.
  • Clean energy alternatives.
  • Climate Change in the Bay of Islands
  • The Author. Bob Bingham.
  • Satellite accuracy.
  • Reference sites

Bob Bingham Blog page.

A series of opinion pieces on, mostly climate change and related subjects to do with New Zealand.

Back to home page.

Is CO2 killing our rivers?

19/4/2015

0 Comments

 
Picture
Picture
We tend to take the natural composition of rainfall that fills our rivers and streams as a constant but, like a lot of things today, that is no longer the case.

A healthy stream should be slightly alkaline and have a pH level in a range of between 7.2 and 8.0 (7 is neutral) but water that falls as rain has washed CO2 out of the atmosphere and is slightly acidic at 5.7.  This acidic rainwater is made more alkaline and moved to 7.2+ by washing minerals out of the rocks and soil and the addition of organic matter from trees and grasses.

Picture
Organisms living in the streams are comfortable in alkaline water at pH levels above 7.2 and at that level will thrive. The smaller invertebrate of mayfly, caddisfly larvae and stonefly are the key here as they form the base of the fresh water fish food chain and also are sensitive to water quality. They could be called the canary in the coal mine, if the canary dies the miner is likely to die as well. 

The current level of CO2 in the atmosphere has just reached 400 ppm compared to its natural high of 280 ppm, 150 years ago before we started burning coal. This has raised the acidity of fresh water from the atmosphere by 33%.

Rivers and streams are hugely variable but never the less this big change in acidity must be affecting the natural habitat of our freshwater aquatic life in much the same way that ocean acidity is affecting our mussels and corals and anything else with a calcium carbonate shell like plankton.


Picture
This chart from NOAA illustrates how not all fresh water aquatic life can survive a change to more acidic water and as with the oceans if the smallest creatures can not survive the base of the food chain is cut off.

The big increase in the amount of nitrogen from cattle effluent is well recognised for the damage it does, but acidity increases from atmospheric CO2 are not so well reported and yet need just as much attention.
It highlights the necessity of looking after the streams we have and treating a health stream as a resource to combat increasing spells of drought caused by a warming world.
0 Comments



Leave a Reply.

    Bob Bingham 

    Occasional blog posts on topical news items concerning the climate.  Please click the RSS feed to receive updates.

    Picture

    Archives

    January 2023
    November 2022
    June 2022
    May 2022
    May 2021
    May 2020
    April 2020
    March 2020
    September 2019
    December 2018
    April 2018
    March 2018
    January 2018
    December 2017
    September 2017
    June 2017
    April 2017
    March 2017
    February 2017
    January 2017
    December 2016
    November 2016
    October 2016
    August 2016
    July 2016
    June 2016
    May 2016
    April 2016
    March 2016
    February 2016
    January 2016
    December 2015
    November 2015
    October 2015
    September 2015
    August 2015
    July 2015
    June 2015
    May 2015
    April 2015
    February 2015
    January 2015
    December 2014
    November 2014
    October 2014
    September 2014
    August 2014
    July 2014
    June 2014
    May 2014
    April 2014
    March 2014
    February 2014
    September 2013
    May 2013
    April 2013
    March 2013

    RSS Feed

    Categories

    All
    Clean Water
    Climate Change.
    CO2 Levels
    El Nino
    Floods
    Methane
    Ocean Acidity
    Pine Island Galacier
    Sea Level Rise
    Soil Loss
    Storms

    RSS Feed

Proudly powered by Weebly