Not cooling off

Updated One of the cheapest arguments raised against global warming is to point to some place somewhere where it is unusually cold at that moment and sneer something like "oh, yeah, global warming, sure, tell it to" whoever is cold just then. The argument is, naturally, bogus, as the warming is an overall average, not something that applies to every single place every single day. Even year-to-year comparisons are really too short-term to be truly revealing. But when there is an overall pattern over a longer term, it tells you something. Here are a few data points to add to that pattern.

- January 5: AFP reported that Australia had just had one of its hottest years ever

and climate experts have warned that the higher temperatures are likely a taste of things to come as weather patterns change.

The country has already kicked off 2008 with a spate of extreme weather - several cities, including Perth and Melbourne, have suffered summer heatwaves, while bushfires have raged on the east and west coasts,

along with flooding and heavy rains in areas. While overall, it was the sixth warmest year on record in Australia,

[i]n the southern states of New South Wales, Victoria and South Australia, as well as the major agricultural zone, the Murray Darling Basin, the effect was more pronounced.

These areas, which account for the majority of Australia's 21 million people and 75 percent of the country's irrigated farmland, experienced their hottest year since records began in 1910.

- February 7, again via AFP, comes news that 2007 was the hottest year on record for Shanghai, where the records go back to 1873. The average temperature of 17.8C (64F) was a full two degrees above the long-term average.

Temperatures in China in 2006 were the warmest in 55 years, according to official data, while large swathes of the country last year endured devastating droughts and floods that Chinese scientists linked to global warming.

- March 20, the first day of spring, was observed by The Independent (UK) by describing how spring

is starting to dissolve as a distinct season as climate change takes hold.

According to documented observations throughout 2007 and 2008, events in the natural world that used to be key spring indicators, from the blooming of flowers to the appearance of insects, are now increasingly happening in what used to be thought of as mid-winter, as Britain's temperatures steadily rise.

The increase in winter temperatures has been "startling," the paper says, and is

clearly visible when current monthly means are compared to the average for 1961 to 1990.

To take the figures for last winter from the Central England Temperature Record, the world's oldest, which dates back to 1659: January 2007 was 3.2C warmer than the 1961-90 average, February was 2.0C warmer, March was 1.5C warmer, and April was 3.3C warmer. So far this year, January has been 2.8C above the 1961-90 average for the month, and February, 1.6C.

Those are substantial rises.

They are indeed and they are already contributing to shifts in natural patterns of nature, mostly in southern England, affecting when flowers and trees bloom, insects appear, birds lay their eggs; they're even changing the migratory habits of some butterflies. It may seem quaint to hear spring birds all winter long, but the fact is that if some cycles - say, the life cycle of some insect - get out of sync with some others - say, birds that feed on those insects - the results could be very serious. Say, farm fields innundated with insects. Or starving birds. Or both.

Like the commercial used to say, it's not nice to fool Mother Nature.

- April 17 saw the release of a report from NOAA's National Climatic Data Center that March 2008

was the warmest March on record over land surfaces of the world and the second warmest overall worldwide.

Land temperature was 1.8C (3.2F) warmer than the 20th century average.

Overall land and sea surface temperatures for the world were second highest in 129 years of record keeping, trailing only 2002, the agency said.

Of course, one hot year does not prove global warming any more than one cold year disproves it. But again, these are just more data points on top of a mountain of other data points.

Footnote the Oneth: The nanny-nanny naysayers might insist on pointing out with their familiar snicker that after completing its hottest year on record, in January Shanghai and the rest of southeast China suffered snow and ice storms that crippled power and transport networks. What they likely won't point out is that because of a warm March, snow cover on Asia was at a record low.

Footnote the Twoth: This doesn't really relate to current temperature data, but it's the most appropriate spot for it.

- February 1 brought news via UPI that

[i]ce cores from Greenland and Antarctica show that Earth warmed faster in the 20th century than at any other time in the past 22 millennia, researchers said.

What's more, the concentration of greenhouse gases is increasing much faster than in times past. The fastest growth in CO₂ concentration before the industrial era was an increase of 31 parts per million over some 1,600 years - an increase matched over the last 20.

Updated with links to NOAA and to its National Climatic Data Center, which I forgot to include originally.