Jennifer Marohasy

a forum for the discussion of issues concerning the natural environment

Archives for March 2, 2009

Global Warming in Perspective: A Note from William Happer

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“BUT the climate is warming and CO2 is increasing. Doesn’t this prove that CO2 is causing global warming through the greenhouse effect? 

“No, the current warming period began about 1800 at the end of the little ice age, long before there was an appreciable increase of CO2. There have been similar and even larger warmings several times in the 10,000 years since the end of the last ice age. These earlier warmings clearly had nothing to do with the combustion of fossil fuels. The current warming also seems to be due mostly to natural causes, not to increasing levels of carbon dioxide. Over the past ten years there has been no global warming, and in fact a slight cooling. This is not at all what was predicted by the IPCC models.”

So explained William Happer, a professor of physics at Princeton University, to the U.S. Senate Environment and Public Works Committee on February 25, 2009.

[Read more…] about Global Warming in Perspective: A Note from William Happer

To Tax or Trade Carbon

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Australian economist Alan Moran considers the advantages of taxing versus trading to reduce carbon emissions and concludes the best policy for Australia is to do nothing till 2020, then catch up by 2050, given the Treasury’s estimate at 3 percent of GDP.  Read more here.

Shark Numbers and Shark Attacks

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THERE have been three shark attacks in Sydney waters over the last three weeks, but there is no agreement as to whether shark numbers are on the increase – or not.

According to NSW Deputy Premier, Carmel Tebbuts, there is no evidence of increased shark numbers in NSW but Ms Tebbuts does admit cleaner waterways around Sydney (via SMH).

According to the Department of Primary Industries chief scientist, Steve Kennelly, because waters are cleaner there are more sharks.  Hang on! This is not what the Deputy Premier said.

Professor Kennelly explained we are seeing a healthy ecosystem, “to the point where we’re getting whales underneath the Sydney Harbour Bridge and … lots of good bait fish coming in, tailor, king fish and so on and sharks feed on those things (via ABC).

Professor Kennelly did not mention that there have also been bans on commercial fishing in Sydney Harbour since a dioxin scare in January 2006 – this would also probably mean more fish.  

According to Professor Kennelly not even new bans on hunting sharks (due to new fishing quotas) will impact on the risk of shark attacks (also via ABC Online).  

Let’s summarize, sharks eat fish, so if there are more fish you might expect more sharks, add to this, new bans on hunting sharks, so again expect more sharks.   More sharks might increase the risk of shark attacks.   “Nah”, suggest some bureaucrats and politicians!

Wouldn’t it be better if government admitted that policies intended to increase the numbers of fish and sharks, are having an effect, and so the risk of shark attack could increase – and then explain how to mitigate like not swimming at dawn or dusk.