Climate Change Flooding Risk Underestimated

The BBC, citing a study in Nature, informs us that climate change models have underestimated the risk of flooding. High atmospheric carbon dioxide levels mean plants suck less water out of the soil. Wetter soil means faster soil saturation in heavy rains, hence more serious flooding.

From the BBC:

Researchers say efforts to calculate flooding risk from climate change do not take into account the effect carbon dioxide (CO2) has on vegetation.

Higher atmospheric levels of this greenhouse gas reduce the ability of plants to suck water out of the ground and “breathe” out the excess.

Plants expel excess water through tiny pores, or stomata, in their leaves.

Their reduced ability to release water back into the atmosphere will result in the ground becoming saturated….

The higher the level of atmospheric CO2, the more the pores tighten up or open for short periods.

As a result, less water passes through the plant and into the air in the form of evaporation. In turn, this means that more water stays on the land, eventually running off into rivers when the soil becomes saturated.

The upside is that wetter soil should reduce the severity of droughts, but with higher temperatures, it’s not clear whether that effect is net positive.

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  1. Anonymous

    we have received more rain in the last six weeks than we have received in the previous six months.

    also the amount and rate of the rainfall has broken all records.

    we have recieved over sixteen ( 16 ! ) inches of rain in August here in the Upper Midwest usa.

    good thing that Global Warming / Climate Change is an Urban Myth otherwise we might start to worry.

  2. jan perlwitz


    you say:
    “good thing that Global Warming / Climate Change is an Urban Myth otherwise we might start to worry”

    Oh, interesting! I haven’t known that. How do you know Global Warming is an Urban Myth? Obviously, the climate scientists haven’t got the message yet.

  3. Anonymous

    well, the Republican Party ( GOP ), conservatives, reich wingers and all sorts of monied interests ( amerikan corporations, etc ) tell the amerikan sheeple over and over and over that this Global Warming / Climate Change stuff is all made up fantasies of eco-terrorists – if that is what the rich folk believe and propagandize, then that is good enuff for me !!!!!!!!!!!!

  4. Charles Butler

    All of the above OT’s, of course. The item didn’t deal with global warming, but rather co2 levels in the atmosphere.

    Thanks for your valuable contributions, regardless.

  5. jan perlwitz

    @charles butler:

    The item dealt with CO2-levels in the context of global warming/climate change what you easily will see when you go to the BBC-article.

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