What Causes Climate Change?

With all the massive publicity given to the issue of climate change, in particular global warming, over the last decade, it's an important exercise to look at the possible causes of this, particularly as it now has assumed major international political dimensions.

We can talk about “temperature change” in close parallel with “climate change” as temperature is the main driver of our climate system. Changes in temperature patterns produce a large variety of “knock on” effects such as variations in rainfall, humidity, snow, cloud cover and wind regimes around the world.

We know from so called proxy data that global temperatures have varied considerably across the known history of the Earth, over periods of millions of years. Climatologists studying such data as ice cores, rock structure, lake sedimentation, glaciers, fossils and tree rings have been able to build up at least a rough picture of our past temperature patterns.

From what we understand, the temperature time line of planet Earth looks something like this – where "mya" means “million years ago”. The reference line shown in red is the present global temperature and we see there are numerous instances where this line has been exceeded (warm epochs) and others when the reverse is the case, the times of Ice Ages.

The obvious question follows – what could be producing these variations?

In fact several likely causes have been identified, all of them entirely natural except one where climate scientists say there may be a human “footprint” – the so called anthropogenic effect.

This is a summary:

Milankovitch cycles: A sequence of “wobbles” of the Earths rotational axis and irregularities in its orbit around the Sun that occur over long periods and were first identified by the Serbian astronomer Milutin Milankovitch early in the 20th century. These cycles produce periods of warming and cooling in the Earth’s climate over time scales of several thousand years.

Serbian scientist Milutin Milankovitch - discoverer of the so - called Milankovitch cycles. (Image from Wikipedia commons)

Impact from extra terrestrial bodies: Large meteors and possibly even comets have collided with the Earth over past millions of years and these have strongly affected the climate. With a collision of this type a vast amount of debris is injected into the atmosphere and this can shield the surface of the Earth from solar radiation for extended periods, resulting in substantial cooling. It is suspected that one such collision around 65 mya produced a much cooler global climate for several thousand years, resulting in the demise of the dinosaurs.

A NASA impression of the giant collision of 65 mya that led to the extinction of the dinosaurs. (Image form Wikipedia Commons)

Continental drift: The world’s great continents actually move relative to each other at very slow rates of only a few millimetres a year. But over millions of years this movement becomes significant with different distributions of land and ocean resulting and changed patterns in ocean currents. These currents flowing around the world play a major role in transferring surface heat from tropical latitudes towards the polar regions and these have a major impact on climate patterns. The Gulf Stream, for example, produces much warmer weather for the United Kingdom and western areas of Scandinavia than areas of similar latitude in Canada. Disruption of these ocean currents, caused by continental drift, would certainly produce significant climate change.

Volcanoes: In a similar fashion to meteor impact, volcanic eruptions can inject massive amounts of dust into the atmosphere that result in solar shielding and global cooling. The 1815 eruption of Mount Tambora in Indonesia was a major cause of the so-called “Year without a summer” in 1816, when abnormally cold temperatures spreading across England and Europe produced widespread crop failures and famine.

The Mt. Pinatubo eruption in the Philippines, 1991. (Image from Wikipedia Commons)

Cosmic rays: These are high-energy particles that constantly bombard the Earth’s atmosphere. They are thought to originate from outside our solar system and could be produced by massive supernovae, or stellar explosions, from far distant stars. It has been speculated that the “gusts” and “lulls” in cosmic ray activity could produce climate change but this remains an area of controversy.

Variation in solar power: Observations in the power output of the Sun shows it to be variable with several known cycles. These include those of 11 years, 88 years, 208 years and 1000 years. There are probably more and these would have some type of impact on our temperature and climate system, although the specifics are far from clear

The Sun - power emitted varies over several different time scales (image from Wikipedia Commons)

Changing gas concentrations within the atmosphere: Our atmosphere contains a mixture of gases, with the so called “greenhouse gases “, including water vapour, carbon dioxide and methane, playing a major role. These gases prevent a total escape of solar energy back out into space and keep our global temperature warmer than it otherwise would be. Climatologists are worried that by the constant burning of fossil fuels we increase the concentration of carbon dioxide and thereby raise global temperatures. This mechanism for climate change, if real, is notably different to others in that it is produced by human activity rather than the natural processes already noted. This is known as the anthropogenic effect.

For information on how past climates have been measured go to:

http://passingparade-2009.blogspot.com.au/2009/08/measuring-past-climates.html

Bring Back National Service?

National Service has always been a highly contentious matter in Australia, particularly during the Vietnam War era when 20-year old conscripts were required to become combat soldiers in a real “shooting war”.

Ultimately some 63,000 young men were called up between 1965 and 1972 and 15,380 served in Vietnam. 184 National Servicemen died there and 880 were wounded in action.

Australian troops arrive at Saigon Airport 

during the Vietnam War - Wikipedia image

Towards the end of the war the opposition to sending conscripts to Vietnam had become very strong, with several large public demonstrations taking place in capital cities and organisations such as the “Save our Sons” group gaining considerable support.

The war had become generally unpopular by 1972, to such an extent that the then leader of the Opposition, Gough Whitlam, made the ending of conscription one of his key election issues. It certainly did play a significant part in producing a change of Government, and primarily for this reason successive political parties have steadfastly avoided any plans for the reintroduction of National Service.

The Hon. Gough Whitlam, 21st Prime Minister of Australia

(Wikipedia image)

But perhaps it was not National Service, as such, that was the basic problem, but more the way it was implemented. The selection system, involving the drawing of a marble from a Tattersall’s lottery barrel, provided a date and all 20 year old men whose birthday fell on that date were called up. The Leader of the Opposition in 1965, Arthur Calwell, described this system as the ‘lottery of death’.

Then there was the fact that conscripts were sent into a war zone. It’s bad enough when an Australian soldier is killed in an overseas war, but when a National Serviceman is killed in action, the situation becomes political dynamite.

But National Service does not have to be like this. There are ways of instituting a system that avoids these highly contentious issues and is still of considerable benefit to both the individual and to the nation.

Various schemes have been suggested over the years and here is one of these.

A call up for all twenty year olds is instituted – men and women – with the requirement for a three - month period of service. The inductee would have a choice of various electives and these could be chosen from the following areas:

The Army – a basic training course

Community work – Meals on Wheels, shopping and gardening for the elderly, work in nursing homes, Salvation Army, Vincent de Paul.

Council work – bushland regeneration

State Emergency Services (SES)

Rural Fire Services (RFS)

If Australia is involved in armed conflict at the time there would be no requirement for the conscript to become involved unless he or she volunteered and this would require leaving the National Service scheme and joining the regular Army.

“Points” could be attached to these activities depending on Government priorities, and

after a certain number was amassed, the conscript would be entitled to a subsidised home loan.

The SES in Victoria attend a vehicle accident

(Wikipedia image)

Such a scheme would be of considerable benefit to the nation. We would develop a large number of young people with basic military training that could be of great assistance in the event of mobilisation. Work in the SES and Rural Fire Services would improve our responses in emergency civil situations.

A considerable amount of useful community work would be undertaken – work which is presently in “on hold” because of the lack of people power.

And finally, such work would be of great benefit to the individual. Apart from the character building and discipline that comes from involvement in work of this type, unique networking opportunities arise from the mix of people that comes with National Service.

Would it work?

Ask not what your country can do for you – ask what you can do for your country - President John F. Kennedy, January 20^th 1961.

Drunk in Parliament - Disorder in the House

In recent times allegations have flown regarding Members of the NSW Parliament being drunk in the House, and this has led to speculation about declining standards of behaviour amongst our leaders.

But we needn’t worry too much – the Parliamentarians of today are mostly model citizens compared to many of their 19^th century counterparts.

Cyril Pearl in his “Wild Men of Sydney” described the NSW Parliamentary scene of the 1880’s as anything but an edifying spectacle.

NSW Parliament House, Macquarie Street, Sydney c 1895. (Charles Kerry Photograph)

“Violent behaviour and violent language were condoned or scarcely rebuked; fights between members were not uncommon and the sight of a drunken statesman falling off his bench during a debate excited amusement rather than indignation”.

The association between alcohol and legislation was a strong one and regarded as entirely normal. Pearl recounted that “…..a timid proposal that grog should be banned in the Parliamentary refreshment room was easily defeated”.

Sir John Robertson, Premier of NSW on five different occasions during the 19^th Century, remarked that “None of the men who in this colony have left footprints behind them have been cold water men”. Sir John restored the financial affairs of the Reform Club, when as President, he advised the members that “We must drink the bloody club out of debt”.

Sir John Robertson, Premier of NSW, c 1880. (Image from Wikipedia Commons)

The newly elected Adolphus Taylor told his supporters in 1882 that “Mudgee is represented by three good drinking men – myself, Sir John Robertson and David Buchanan”.

But perhaps the most notorious drunkard in the House was John Norton, editor and owner of the “Truth” newspaper and Member for Sydney-Fitzroy in 1898. On one occasion, during Parliamentary debate, he was removed from the House for “shouting drunkenly, to Mr. J. C. Watson, “Damn and f..  you” , and on the last night of the session he was so drunk that he urinated on the floor of the Chamber. Pearl recorded that he was then “dragged out by two constables to the accompaniment of salvos of ripe oaths and the crash of broken glass…”

John Norton, Member for Fitzroy, c 1898.

(City of Sydney Archives, NSCA CRS 54/315

Such lamentable scenes now belong in the past and the average politician of today is a hard working and effective contributor to Australian society. Any lapses that may have occurred over the last few months would barely have raised an eyebrow in the Parliament of the late 19^th Century. The election of women Members to the House has undoubtedly helped raise the standards of behaviour in this respect.

The Oklahoma and Tri-State Tornados

The catastrophic tornado that descended on Moore, Oklahoma on May 20^th 2013 was one of the most intense yet observed. Now officially rated as an EF 5 system, the highest on the tornado rating scale, it is believed to have generated surface winds of around 340 km/hr (210 mph).

The tornado as it moved to the southwest of Moore - image from Wikipedia Commons (click to enlarge)

The funnel was estimated to have been more than 2 km (1.3 miles) across and during its 50-minute life span travelled some 27 km (17 miles), including a rampage across the highly populated Moore area.

The tragic death toll is, at the time of writing, 24 and more than 200 people were injured.  The damage bill will run into billions of dollars.

Comparisons with the infamous Tri State tornado of March 18 1925 have already been made. In this event a twister ripped through some twenty sizeable townships, including Gorham, Murphysboro, De Soto, West Frankfort and Parrish, all in southern Illinois, causing utter destruction right across the area.

Eventually the tornado crossed the border into Indiana, where it inflicted massive damage to the townships of Griffin and Princeton, before finally abating, after the longest continuous rampage of any known twister.

Contemporary newspaper article following the Tri State tornado of 1925 - image from Wikipedia Commons (click to enlarge)

Subsequent investigation of the damage trail revealed a monstrous gouge of destruction across the countryside, some 353 km (219 miles) long and about 1.2 km (three quarters of a mile) wide. From existing photographic evidence of the damage produced, experts have rated the Tri State as an F5 tornado.

In all, 695 people died - still the record by far for an American tornado. Over 2000 were injured and some 15,000 homes demolished.

It is difficult, if not impossible, to directly compare these tragedies, but one statistic does stand out – the massive difference in the death toll. During the Tri State event there was no organised tornado warning system, no radar imagery and no satellite photographs available. This twister struck virtually without warning.

For the Oklahoma event, effective short-term warnings were issued by the US National Weather Service and these, without doubt, saved many lives. The great strides in public education about tornados, as conducted by the Weather Service and other Government agencies have also been most effective. And this, together with publically available information on the Internet, plus the training and skill of the National Weather Service meteorologists, helped prevent another Tri State scale death toll.

The logo of the National Weather Service of the United States - image from Wikipedia Commons (click to enlarge)

Unfortunately tornados are part of the climatology of the southern parts of the United States but improved forecasting skill, together with technology and public education is making a real difference. Our hearts go out to the people on Moore in Oklahoma who have been devastated by this event.

For an Australian example of the increased effectiveness of weather forecasting see:

http://passingparade-2009.blogspot.com.au/2011/02/yasi-versus-tracy-tale-of-two-cyclones.html

Meteorite Rocks Russia

On Friday 15^th February 2013, locals in the Russian city of Chelyabinsk were astonished to see a blinding light streak across the sky in the early morning glow, with a brightness rivaling that of the sun itself. Soon after, amid noises of rolling thunder, the ground shook, buildings swayed and windows shattered. It turned out later that some 1200 people had been injured, mostly by falling debris and flying glass from damaged buildings.

Reconstructing this extraordinary event, scientists concluded that the event was generated by a meteoroid exploding above the ground, producing a giant shock wave that blasted downwards and outwards and generating energy similar to that of a small nuclear explosion.

Planet Earth is enshrouded by a protective blanket - the atmosphere – that enables life as we know it, in all its forms, to exist. But of equal importance it provides an invisible shield that protects us from the fusillade of rocks called meteoroids that constantly bombard us from outer space.

When a meteoroid enters the atmosphere, travelling at speeds normally in excess of 50,000 km per hour, it begins to burn up because of friction with the atmospheric gasses. This produces a bright streak of light across the sky that is normally only visible at night. If you are to go outside on a clear night and observe the sky for a period of half an hour or more you will usually see one or more of these luminous, transient streaks that usually only last for less than a second. This streak of light is known as a meteor.

A meteor in the night sky

(Image form Wikipedia Commons)

In most cases the chunk of rock will burn up or vaporize before reaching the ground, and it is this protective property of the atmosphere that has played a big part in the survival of life on the planet. Without it we would look like the Moon that has no such protection and is pockmarked with impacts from many thousands of meteoroids.

In some cases fragments will reach the surface of the Earth as a shower of rocks called meteorites and these are always interesting to scientists as they are ancient objects from the far flung reaches of outer space and often have a different structure and composition to rocks we find on Earth.

The surface of the Moon - scarred by countless meteoroid impacts.

(Image from Wikipedia Commons)

On rare occasions much larger meteoroids will enter the atmosphere, with a size big enough to prevent complete vaporization and these will reach the lower levels of the atmosphere partially intact and still travelling at tremendous speed. One of two things usually follows.

The first is what probably happened over Chelyabinsk – a massive mid air explosion that generates a blindingly bright flash, together with a shock wave and sound of rolling thunder. Smaller rock fragments will then shower across the area as meteorites. 

Russia was also the scene of another such event in 1908 when a monstrous air burst explosion over the Tunguska area produced a massive shock wave that flattened huge tracts of pine forest in the area, affecting a zone of around 2000 square kilometers. This was a much more powerful event that Chelyabinsk incident.

But what can also happen is when the rock remains largely intact all the way to the surface, eventually striking the ground with colossal force and producing a large impact crater. It has long been believed that an event such as this some 65 million years ago produced a cataclysmic explosion of such a scale that the atmosphere around the world was affected, with the extinction of the dinosaurs a consequence.

As a testament to this type of event, large impact craters can be found today, including “Meteor Crater” near Winslow, Arizona that was created about 50,000 years ago when a large meteorite slammed into the area. The crater is about 1.2 km across and 170 m deep.

Above: Meteor Crater, Arizona. (Image from Wikipedia Commons; Click to enlarge)

In Australia, Wolfe Creek is a large crater located in the desert of Western Australia about 150 km to the south of Halls Creek. It is estimated that this crater was produced by a meteorite that had a mass of some 50,000 tonnes striking the surface around 300,000 years ago. The crater is about 900 metres across and 60 metres deep.

Above: The Wolfe Creek Crater, Western Australia

(Image from Wikipedia Commons; click to enlarge)

What would happen if such an object were to stroke a modern city – such as Sydney or Melbourne? Well, the short answer is - disaster. The actual impact crater would take out a suburb, and the associated shock wave and impact vibrations would likely destroy much of the city. So should we be concerned?

Well the short answer to this is no. Events of such as Meteor Crater and Wolfe Creek probably only occur only about once every 50,000 years or so, and in the great majority of any future cases the actual impact point would be in non-urban area. You have more of a chance of being struck by lightning or kicked to death by a donkey that dying through meteorite impact.

Swing Bowling

In most top class cricket teams today there is at least one swing bowler, one who can move or “swing” the ball from its initial line in the air, producing a difficult situation for the batsman, both from a scoring point of view and also just to survive at the crease.

One of the earliest exponents of swing bowling was the great Australian pace-man Frederick “The Demon” Spofforth (1853 – 1926), who began his spectacular Test career in 1877 at express pace, but later switched to variation in his bowling, including a mean in-swinger that produced plenty of wickets. 

Frederick Spofforth (1853 to 1926)

Test bowler for Australia - known as "The Demon"

(Image form Wikipedia Commons)

Known as “swerve” in the 19^th century, it was further developed over the years and is now recognized as one of the main weapons in the arsenal of the fast medium bowler. The English quick James Anderson is recognized as one of the great swing bowlers of the present time.

Swing bowling is very much an art, and is produced through several different factors, including the way the ball is held on delivery, the nature of the shine on the ball, and perhaps a little more surprisingly, the weather.

English fast bowler James Anderson - a noted swing bowler

(Image form Wikipedia Commons)

Bowling a swinger basically depends on the position of the seam on the ball through the delivery and this results in one side travelling through the air faster than the other. This is encouraged by polishing one side of the ball and assisted by the prevailing atmospheric conditions such as temperature, humidity, cloud cover, together with wind speed and direction.

The denser the air, the more swing is encouraged, so cooler air is a more fertile swing environment than warmer air. Up until quite recent times it was also believed that high humidity helped in encouraging swing, but new research has revealed the rather surprising fact that cloud cover may be far more important. In bright sunlight hot air rises from the surface of the pitch, creating a turbulent environment for the ball to pass through, which reduces swing. In overcast conditions there is less rising air, less turbulence and more swing.

All this means that cool, overcast weather is best for swing bowling and the swing can also be magnified if there is some component of the wind blowing across the wicket in the same direction in which the ball is swinging.

These conditions are met with far more often in England than Australia where hot and sunny weather is the norm during the summer months, but on occasion good swing bowling weather can emerge here as well. In the southern capital cities of Australia, such as Adelaide, Hobart, Melbourne and Sydney, this can happen in a southerly airflow following a cold front, when temperatures fall and cloud cover increases.

One of the greatest exhibitions of swing bowling ever seen was by the Australian Bob Massie in the Second Test at Lords in England during the 1972 Ashes tour.

In cool and cloudy conditions, Massie, coming alternately over and around the wicket, bent the ball through the air so prodigiously that many of his deliveries were virtually unplayable and the English batting was routed. His figures over the two innings were 8/84 and 8/53, representing match figures of 16/137, the third best test match figures of all time.

Massie’s display was a convincing demonstration of the tremendous potency of swing bowling, achieved when the bowler is on song and the atmosphere is just right for the purpose.

Great footage of Massie’s bowling during this Test can be seen at

http://www.youtube.com/watch?v=g_mAF2-PKew

在澳大利亚的中国

中国在澳大利亚的历史是一个有趣的。有几个中国人抵达澳大利亚在1800年初，但发现于1852年在澳大利亚农村地区的黄金生产的大量涌入，所有的金矿尝试自己的运气。

虽然很多最终还是回到了中国，中国移民搬离金矿和在悉尼附近开设小型企业，包括食品商店，并提供招待所。此外，中国市场花园窜出了在悉尼的郊区，蔬菜种植，后来在市场出售。中国人也开辟了家具制造工厂，在那里好，价格便宜的家具制造。

中国市场的园丁，悉尼，1893年

社区领袖，包括餐馆老板美梅光达在1890年的悉尼成为一个成功的受人尊敬的商人。男人像他那样多，逐步打破了当地对中国社会的偏见，它被越来越多地认识到，绝大多数的中国人的勤奋工作和良好的公民，澳大利亚。

一个皇家委员会在1891年举行“指称中国赌博和不道德”，并发现，中国的房子在悉尼整齐，很好的照顾和谁娶了中国男人的澳大利亚妇女发现他们良好的和有爱心的丈夫。

美梅光达

在中国和澳大利亚之间的关系是一个重要的转折点，当日本侵略中国南京在1937年，中国本土的社会团结。许多中国人参加了澳大利亚军队在第二次世界大战中抗击日本。

悉尼和墨尔本周围的大多数中国反对共产主义和不支持毛泽东政权在20世纪60年代，但在过去的三十年中，政治的情况已经淡化。在悉尼唐人街附近的语言反映了这一点 - 在60年代和70年代，这是几乎所有的粤语，但现在是压倒性的普通话。

在最近的时代，已成为澳洲的贸易联系越来越紧密，中国和这个行业现在是澳大利亚出口的最重要的因素之一。

悉尼的唐人街，一个众所周知的用餐区和旅游景点。

社会上也有显着增加之间的整合与异族通婚越来越受欢迎在过去的三十年，中国和澳大利亚的社区我个人熟悉这是我的女儿在法律上是中国的澳大利亚，当然是我的两个可爱的孙子。


澳大利亚著名的中国公民过去的150年：

美梅光达（1850年至1903年）：在澳大利亚悉尼的中国商人和社区领袖。非常成功的商人

黄如彩（1925年至2009年）：中国澳大利亚曾在澳大利亚军队在第二次世界大战的精英突击队的一员。被授予的杰出行为勋章，英勇的行动和后来的承澳大利亚勋章。

张任谦（1936年至1991年）：中国的心脏外科医生和现代化的先驱，听到移植。获委任为伴侣澳洲的命令。拖马来西亚在1991年申办失败的勒索的罪犯被谋杀。






所以约翰（1946 - ）：中国的澳大利亚商人，并两次当选市长的墨尔本市
















黄英贤（1968 - ）澳大利亚参议员代表南澳大利亚州和一个联邦部长吉拉德政府