Monday, May 05, 2008

Surely Now is a Good Time to Re-Consider Whether Man Has Induced Climate Change

With the Government apparently considering a delay to aspects of the Emissions Trading System - only as a sop to a damaged economy, and because the country faces a dodgy electricity supply situation this winter - perhaps now is a good time to carefully review the evidence on anthropogenic global warming.

The catastrophic predictions of the effect on the New Zealand economy of imposing carbon charges (particularly if relatively speaking, the unilateral imposition of those charges) mean a careful government would examine very carefully the evidence before implementing the change.
A wise government would take the time to consider the null hypothesis.

The Null hypothesis could be:

"Global warming is not due to greenhouse gas produced as a result of human activity"

Why is considering this hypothesis important?

The evidence seem to be that any warming phase has now disappeared.

The Pacific Decadal Oscillation (PDO) is a temperature pattern in the Pacific Ocean that spends roughly 20-30 years in the cool phase or the warm phase.

In 1905, PDO switched to a warm phase.
In 1946, PDO switched to a cool phase.
In 1977, PDO switched to a warm phase.
In 1998, PDO showed a few cool years.

The PDO appears to have flipped and we are in a cooling phase.

The global environment is now apparently in a cooling phase and if it (as might be likely) is a multi-decade phase we'll need to prepare for a cooler climate and possibly more than beanies.

In 2008, PDO seems to be switching to a cool phase. (NASA).

The warm (cool) phase is determined by above-the-average (below-the-average) temperatures along the West Coast of the U.S. and Canada.

Hence the harsh US winter, the recovery of the Arctic sea-ice and so on.

At the same time, a longer cycle oscillation in the Atlantic called the AMO may also be in the cooling part of its oscillation over the next decades.

Thus the PDO mainly affects temperatures around the Pacific Rim - the Pacific is in fact a very large part of the earth - what is the effect/correlation of its cycling on global temperatures?

From the PDO data itself, it is apparently just too soon to be able to tell whether the current cool phase is just one of the shorter cycles, or whether it is the beginning of a longer term cycle observed back in the 1950’s and 1960’s.

Back to the case for carbon madness in New Zealand.

If the case for anthropogenic global warming fails it follows that the ETS can be shelved for good. Ditto coal fired power generation could be back on the agenda.
Ditto the ruinous bio-fuel agenda could be ditched.

Let me state at the outset - I am all for being a good steward of all our resources. We should only use what we need and leave a minimum footprint in all we do.

Considering the power crisis. New Zealand has at least 1,000 years of coal reserves. We are an energy rich country.

Why oh why are we facing a power crisis?

Because Labour policy decisions to impose a moratorium on new fossil fueled base load generation have left the country relying on imperfect lake storage systems. No lake - no power - simple.

If the case for man made global warming was not valid we could have all the power we need.

The evidence is becoming clearer day by day that the warming in the latter half of the 20th Century is normal climate variability. More on this below.

Moving to the case for man made global warming - by the day the case against the IPCC climate change agenda gets stronger.

At every step recently the evidence (note evidence, not projection) is completely counter to any of the published IPCC projections.

Perhaps the most interesting point is the recent warming is ahead of the IPCC scenario it was warmer than the models predicted....I'll come back to that further in this post.

When is the mainstream media and perhaps more importantly governments or opposition governments going to pick up this vital discussion.

The IPCC scenario projections are being proved incorrect as every month goes by. The only response of the IPCC prognosticators has been to say the results are unexpected but have no fear warming will return soon.

The realities:
The mean global surface temperature has been reducing since 1998.

A very good summary by Christopher Brooker of the Daily Telegraph states:

A German study, published by Nature last week, claimed that, ...(the world) may cool down until 2015 "while natural variations in climate cancel out the increases caused by man-made greenhouse gas emissions".Two weeks ago, as North America emerged from its coldest and snowiest winter for decades, the US National Climate Data Center, run by the National Oceanic and Atmospheric Administration (NOAA) issued a statement that snow cover in January on the Eurasian land mass had been the most extensive ever recorded, and that in the US March had been only the 63rd warmest since records began in 1895.

On April 24 the World Wildife Fund (WWF) published a study warning that Arctic sea ice was melting so fast that it may soon reach a "tipping point" where "irreversible change" takes place. This was based on last September's data, showing ice cover having shrunk over six months from 13 million square kilometres to just 3 million.

What the WWF omitted to mention was that by March the ice had recovered to 14 million sq km (see the website Cryosphere Today), and that ice-cover around the Bering Strait and Alaska that month was at its highest level ever recorded. (At the same time Antarctic sea ice-cover was also at its highest-ever level, 30 per cent above normal).

The most dramatic evidence, however, emerged last week with an announcement by Nasa's Jet Propulsion Laboratory that an immense slow-cycling movement of water in the Pacific, known as the Pacific Decadal Oscillation (PDO), had unexpectedly shifted into its cool phase, something which only happens every 30 years or so, ultimately affecting climate all over the globe.

Discussion of this at Watts Up With That website, run by the US meteorologist Anthony Watts, shows how the alternations of the PDO between warm and cool coincided with each of the major temperature shifts of the 20th century - warming after 1905, cooling after 1946, warming again after 1977 - and how the new shift to a cool phase could have repercussions for decades to come.

It is notable that the German computer predictions published last week by Nature forecast a decade of cooling due to deep-ocean movements in the Atlantic, without taking account of how this may now be reinforced by a similar, even greater movement in the Pacific.

Mr Watts points out that the West coast of the USA might already be experiencing these effects in the recent freezing temperatures that have devastated orchards and vineyards in California, prompting an appeal for disaster relief for growers who fear they may have lost this year's crops.

The fact is that what has been happening to the world's climate in recent years, since global temperatures ceased to rise after 1998, was not predicted by any of those officially-sponsored models.

Returning to my note above that the measured warming in the later period of the 20th Century was ahead of the IPCC scenario projections:

Perhaps the most cogent view on the forcing effect of normal climate variability is a comment by a reader at Climate Audit

“One of the reasons I got annoyed with the IPCC when I was involved, was an almost universal dismissal of the contribution of natural forcing to the observed warming - particularly the role of decadal-scale climate variability such as the PDO. In discussions with one of our Nobel Peace Prize winning meteorologists back in the 1990s, their position was that the greenhouse effect had overwhelmed natural variability and it just would not be possible for the PDO to switch.”
This is important - the recent warming was higher than the IPCC models predicted. Perhaps, just perhaps the warming was an outcome of natural variability in the ocean?

Rather than investigate, the warmists said greenhouse effects had overwhelmed natural variability....

So what is causing the cooling phase clearly in evidence?

Ya can't have it both ways.

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