Get ready — for all the fears of extreme weather coming our way — studies of Queensland, Victoria, the whole of SE Australia, New Zealand, and Perth show that either nothing is changing (there have always been bad storms) or possibly, the weather is better now than it used to be. Where is the evidence to support the claims by alarmists that increasing CO2 will make “extreme weather” more common?
It’s less windy now across South East Australia than it was in the 1920′s. It’s less stormy on the southern coast of Victoria, and records that go back 7000 years in New Zealand and 5000 years in Queensland show repeated examples of monster storms that — should they hit today, would be described as being “likely” due to coal fired power stations and excessive use of SUV’s.
The Science and Public Policy Institute published Historical storm trends in Australia and New Zealand in June. This post builds on that publication.
It’s less windy across South East Australia
Alexander et al 2011 looked at locations from Port Lincoln (SA) to Goondiwindi (QLD), to Hobart (Tas) which pretty much covers everything anyone could call South East Australia. They used wind speeds from as far back as records could go (1890 onwards) and the results showed the wind speeds have declined across the whole region. Furthermore it doesn’t matter what season you study. The trends are the same.
For those who are old enough to say so, “yes” it really was stormier and windier back in the 1920′s in Australia.
But what about the long long trend? Say 5000 years?
Hayne and Chappell (2001) looked at deposits left from storm surges on Curacoa Island (one of the Palm Islands of far north Queensland). They found that large cyclones have been hitting the coast at a statistically constant rate for 5000 years. This includes the earliest times when the sea surface temperature appear to have been about 1°C warmer (Gagan et al 1998). At Palm Island, sea levels were apparently 70cm higher back in that warm Holocene era (Chappell et al 1983). Somehow the Great Barrier Reef survived.
Haynes writes: ” This suggests that cyclone frequency may not have been affected by sea surface temperatures in the region.”
Nott and Hayne studied a 5000 year history of super-cyclones along a 1500 km stretch of North East Australia and concluded that the big nasty ones hit roughly every 200-300 years in all parts of the coastline from 13° – 24°S.
Storms in New Zealand? Not getting worse either in the last 130 years
Even before 1905 when the first car traveled all the way from Wellington to Auckland, bad storms were occurring in New Zealand at about the same rate as they do today (De Lange and Gibb 2000). New Zealand didn’t get it’s first major coal power station until as late as 1958 either. And after coal fired power came on line the New Zealand, the “extremes” of climate apparently kept doing what they had done before.
Likewise the dreaded storm surges and tidal rises in New Zealand remained stubbornly flat or are even falling in trend (De Lange and Gibb 2000)
A 7000 year record of storms in NZ
A study of lake sediments at Lake Tutira NE New Zealand show there have been many stormy periods in New Zealand on and off for 7000 years. The worst was about 2000 years ago. These stormy periods can appear abruptly, though during the warmest periods of the Holocene the years between storms is often larger.
From the abstract of Page et al 2010:
A storm event chronology, supported by twelve tephra and three 14C ages, indicates that storm magnitude and frequency has varied over the last 7200 yr. Twenty-five periods with an increased frequency of large storms occur, typically of decadal to centennial duration. Periods of major storm activity occur at about 500–700, 1100–1250, 1850–2100, 2850–3200, 3600–4000, 4300–4500, 4700–4900, 5700–5900, and 6850–6900 cal. yr BP. Several other local and regional climate proxies record conditions that are consistent with the timing and periodicity of major storms in the Tutira record. A period centred on 2000 yr ago has the highest incidence of storms, with a recurrence of 1storm/2.9 yr.
The West Coast of Australia
Since 1995 there has been no increase in storms around Perth. This seems like an terribly short record, but bear in mind that a third of all our human emissions have occurred since then. So all that CO2 has arrived and there is nothing to show for it.
Victoria is less stormy than it used to be
In Victoria, the number of severe storms affecting the south-west Victorian coast has decreased by around 40% over 1856–2006.
Strangely I can’t find any review or compilation of this Australasian data by the Australian government. Despite all the paid officials and scientists, no one appears to have simply collated the relevant studies. If you think these collections of papers and graphs are useful, especially in the current political climate, all contributions are gratefully received. Even a few dollars counts. — Jo
Acknowledgement: Thanks especially to Mark at UWA for assistance.
Thanks to Bob at SPPI for the inspiration and info.
Alexander, L.V. and Power, S. (2009) Severe storms inferred from 150 years of sub-daily pressure observations along Victoria’s ‘Shipwreck Coast.” Australian Meteorological and Oceanographic Journal 58: 129-133. [PDF]
Alexander. L.V., Wang, X.L., Wan, H. and Trewin, B. (2011) Significant decline in storminess over southeast Australia since the late 19th century. Australian Meteorological and Oceanographic Journal 61: 23-30.[pdf link]
Chappell, J., Chivas, A., Wallensky, E., Polach, H.A., Aharon, P., (1983) Holovene palaeoenvironmental changes, central to north Great Barrier Reef, inner zone. Bureau of Mineral Resources Bulletin of Australian Geology & Geophysics, 8, 223-235.
De Lange, W.P. and Gibb, J.G. 2000. Seasonal, interannual, and decadal variability of storm surges at Tauranga, New Zealand. New Zealand Journal of Marine and Freshwater Research 34: 419-434. [abstract & PDF]
Gagan, M.K., Ayliffe, L., Hopley, D., Cali, J., Mortimer, G., Chappell, J., McCulloch, M., Head, M.J., (1998) Temperature and surface water balance of the mid-Holocene tropical western Pacific. Science 279, 1014–1018
Hayne, M. and Chappell, J. (2001) Cyclone frequency during the last 5000 years at Curacoa Island, north Queensland, Australia. Palaeogeography, Palaeoclimatology, Palaeoecology 168: 207-219. [Abstract] [Discussion Hayne and Chappell (2001) ]
Li, F., Roncevich, L., Bicknell, C., Lowry, R. and Ilich, K. (2011) Interannual variability and trends of storminess, Perth, 1994-2008. Journal of Coastal Research, 27: 738-745.