More care needs to be taken when repeating myths on climate change (Re: “Worst case sea level rise a myth” CCA, 30 May 2017)
Your writer made two key comments:
- Melting ice doesn’t cause sea level rises because ice melting in water doesn’t raise the total level of liquid.
- His “factual observation” is that in 33 years the ocean “has not risen by one centimetre”
Here are the facts:
- Yes, ice melting in water doesn’t raise the overall level of liquid. However, that’s the not the issue. The issue is the ice above the water line melting – like ice sheets, glaciers, alpine areas and the Antarctic. When these melt – seas rise.
- Water absorbs heat – ice reflects heat. So with less ice, the oceans are absorbing heat instead of reflecting it, increasing the temperature of the planet, accelerating the rate of ice melting.
- He is correct. The seas haven’t risen one centimetre in the last 30 or so years. They’ve actually risen 10 cm in the last 30 or so years, according to the CSIRO.
CSIRO: “Over the last century global average sea level rose by 1.7 [1.5 to 1.9] mm per year, in recent years (between 1993 and 2010) this rate has increased to 3.2 [2.8 to 3.6] mm per year.”
It should be noted it is the United States Government’s National Ocean and Atmospheric Administration (NOAA) making the forecasts about the 2.5 metre increase. Hardly, “Loony left, climate alarmists”.
Finally, all of the talk of in scientific circles is that the rate of ice melting – above the the water line – is accelerating at a rate much greater than previously forecast, leading to forecasts for rises increasing from 70 cm by 2100 (United Nations 2007) to 200 cm to 250 cm by 2100. (Source: Proceedings of the National Academy of Sciences).
Some reality and fact checking before repeating misinformation. They’re dangerous and hamper the effort to get solid policies to address the climate crisis.
Climate Reality Leader – Al Gore’s Climate Reality Project
Student, Master of Environmental Management, UNSW
Member, Labor Environment Action Network
President, Bellinger River Branch, Australian Labor
GLOBAL MEAN SEA LEVEL (GMSL) – 1880 TO THE END OF 2014 (Source: CSIRO)
NOAA forecasts: https://phys.org/news/2017-01-scientists-bar-sea.html
CSIRO history and forecasts : http://www.environment.gov.au/climate-change/climate-science/climate-change-future/sea-level
CSIRO graphs: http://www.cmar.csiro.au/sealevel/index.html
Coffs Coast Advocate: https://www.coffscoastadvocate.com.au/news/sea-level-rise-is-a-myth-reader/3183431/