On Campbell Island in the Southern Ocean, some 400 miles south of New Zealand, is a single Sitka spruce. More than 170 miles from any other tree, it is often credited as the “world’s loneliest tree”. Planted in the early 20th century by Lord Ranfurly, governor of New Zealand, the tree’s wood has recorded the radiocarbon produced by above ground atomic bomb tests – and its annual layers show a peak in 1965, just after the tests were banned. The tree therefore gives us a potential marker for the start of the Anthropocene.

But why 1965? The 1960s is a decade forever associated with the hippie movement and the birth of the modern environmentalism, a sun-blushed age in which the Apollo moon landings gave us the iconic image of a fragile planet framed against a desolate lunar surface. It was also a time when the world was fast globalising, with rapid industrialisation and economic growth driving population expansion and a massive increase in our impact on the environment.

This postwar period has been called the “Great Acceleration”. So the question we’re interested in is whether this step change in human activity left an indelible mark on our planet, one which, if we disappeared today, would still leave a permanent signature in the geological record.

The concept of a human-dominated geological epoch has been around since the 19th century, but the idea that we have created an Anthropocene has recently become more popular in the face of long-term global changes in the environment far beyond what may be considered “natural”. While humans have long had an impact on the planet at the local and even continental level, the scale of modern change is sufficiently large that geologists are considering the evidence to recognise the Anthropocene officially in the geological timescale. They have set the scientific community a major challenge to find a global-wide environmental marker or “golden spike” that represents this crucial change.

A major contender for defining the start of the Anthropocene Epoch is the peak in radioactive elements produced from above ground thermonuclear bomb tests, the majority of which occurred at the height of the Cold War in the early-1960s. The problem from a geologist’s point of view is most of the records of this spike in radioactivity (for example preserved in lake sediments and the annual growth of tree-rings) have been reported from the Northern Hemisphere where the majority of the tests took place. To demonstrate a truly global human impact requires a signal from a remote, pristine location in the Southern Hemisphere that occurs at the same time as the north. This is where our new study comes in.

In the journal Scientific Reports we publish a new record that identifies a radioactive signal preserved from exactly this sort of place: Campbell Island, a rare piece of real estate in the depths of the Southern Ocean.

During the Australasian Antarctic Expedition 2013-2014 we undertook scientific sampling across the island to get a better handle on the scale of environmental change in this most remote of locations. The solitary Sitka spruce is in the southern part of the island. The species is found naturally along the west coast of North America from Alaska to California – it is only in the Southern Hemisphere because humans transplanted it there.

Turney et al , Author provided

Nonetheless, the Campbell Island tree is growing exceptionally well – at a rate five to ten times faster than surrounding native shrubs – which gave us plenty of data to work with. Detailed analysis of the tree’s year-by-year growth shows the peak in radioactive elements took place sometime between October and December 1965, which coincides with the same signal in the Northern Hemisphere. This spruce has demonstrated unequivocally that humans have left an impact on the planet, even in the most pristine of environments, that will be preserved in the geological record for tens of millennia and beyond.

Our research promises to reignite the debate around when humans really became a geological superpower. Should we define the Anthropocene by when humanity invented the technology to make themselves extinct? If so, then the nuclear bomb spike recorded in the loneliest tree on the planet suggests it began in 1965.</s>From Keele University and the “It’s like deja vu all over again” department with the leader of the “ship of fools” thrown in for comic relief. Long-time WUWT readers surely remember the single “Most influential tree in the world” from the Yamal fiasco, where the “signal” in one tree (YAD06) biased an entire paper with a hockey stick shape, making it worthless. Well, here we are again with another single tree used to define the entire globe. Obviously they’ve learned nothing, then again, it’s Chris Turney.

Loneliest tree in the world marks new age for our planet

An international research team, including Professor Christopher Fogwill from Keele University, has pinpointed a new geological age, the Anthropocene.

When humans first set foot on the moon in 1969, the people of that decade thought the world had changed forever. Little did they know the world had already laid down the precise marker of a far greater global change four years earlier, signalling our planet had entered an entirely new geological epoch, a time period defined by evidence in rock layers, the Anthropocene.

That new epoch began between October and December 1965 according to new research published today in Scientific Reports by members of the Australasian Antarctic Expedition 2013-2014, which was co-led by co-author Professor Christopher Fogwill from Keele University.

The researchers were able to mark this profound change so precisely because of a “golden spike” found in the heartwood of a strange and singular tree, a Sitka Spruce found on Campbell Island, a World Heritage site in the middle of the Southern Ocean The spruce is locally referred to as ‘the loneliest tree in the world’ with the next closest tree over 200km away on the Auckland Islands.

The radioactive carbon spike was created by the culmination of mostly Northern Hemisphere atmospheric thermonuclear bomb tests in the 1950s and 1960s. The signal was fixed in the wood of the Campbell Island Sitka spruce by photosynthesis.

Professor Fogwill, Head of the School of Geography, Geology and the Environment at Keele University, said:

Various researchers from around the world have been talking about declaring a new geological epoch called the Anthropocene, indicating the point where human influence on the planet fundamentally changed the natural world. However, for a new epoch to be officially declared there must be a clear and precise “global” signal that can be detected in the geological forming materials of the future. This radiocarbon spike is that signal.

Lead author Professor Chris Turney, from University of New South Wales, said:

In the Northern Hemisphere, the atmospheric radiocarbon peak occurred in 1964 where the signal is preserved in European trees. That same peak took until late 1965 to reach the Southern Hemisphere atmosphere. With that, the signal became global, precise and detectable in the geological record, meaning it fitted the requirements as a marker for a new epoch.

The 100-year-old tree itself is an anomaly in the Southern Ocean. It is naturally found along the North American Pacific Coast but it is credited with being planted on Campbell Island by the Governor of New Zealand in 1901. The oceanic climate has had an unusual effect on the spruce. Although it has grown to 10m tall, the tree has never produced cones, suggesting it has remained in a permanently juvenile state.

Global Peak in Atmospheric Radiocarbon Provides a Potential Definition for the Onset of the Anthropocene Epoch in 1965

Anthropogenic activity is now recognised as having profoundly and permanently altered the Earth system, suggesting we have entered a human-dominated geological epoch, the ‘Anthropocene’. To formally define the onset of the Anthropocene, a synchronous global signature within geological-forming materials is required. Here we report a series of precisely-dated tree-ring records from Campbell Island (Southern Ocean) that capture peak atmospheric radiocarbon (14C) resulting from Northern Hemisphere-dominated thermonuclear bomb tests during the 1950s and 1960s. The only alien tree on the island, a Sitka spruce (Picea sitchensis), allows us to seasonally-resolve Southern Hemisphere atmospheric 14C, demonstrating the ‘bomb peak’ in this remote and pristine location occurred in the last-quarter of 1965 (October-December), coincident with the broader changes associated with the post-World War II ‘Great Acceleration’ in industrial capacity and consumption. Our findings provide a precisely-resolved potential Global Stratotype Section and Point (GSSP) or ‘golden spike’, marking the onset of the Anthropocene Epoch.

So who says 1965 is the beginning of a new Epoch? There’s no consensus, and they can’t even decide if that’s the name. From Wikipedia’s definition of the Anthropocene:

As of August 2016, neither the International Commission on Stratigraphy nor the International Union of Geological Sciences has yet officially approved the term as a recognized subdivision of geological time,[3][5][6] although the Working Group on the Anthropocene (WGA) voted to formally designate the epoch Anthropocene and presented the recommendation to the International Geological Congress on 29 August 2016. In January 2015, 26 of the 38 members of the International Anthropocene Working Group published a paper suggesting the Trinity test on 16 July 1945 as the starting point of the proposed new epoch.[20] However, a significant minority supports one of several alternative dates.[20] A March 2015 report suggested either 1610 or 1964 as the beginning of Anthropocene.[21] Other scholars point to the diachronous character of the physical strata of the Anthropocene, arguing that onset and impact are spread out over time, not reducible to a single instant or date of start.[22] A January 2016 report on the climatic, biological, and geochemical signatures of human activity in sediments and ice cores suggested the era since the mid-20th century should be recognised as a distinct geological epoch from the Holocene.[23]

Turney is just looking to get his name listed as the identifier of the Anthropocene, nothing more. Fortunately, it won’t be decided by him.

The study is nothing but a headline grabber posing as science, just like Chris Turney’s original “Spirit of Mawson” aka “ship of fools” fiasco.</s>Feb. 19 (UPI) -- Scientists have discovered evidence of the beginning of the Anthropocene, the newest geological epoch. The evidence came in the form of a "golden spike" found in the heartwood of the "loneliest tree in the world."

Though scientists have shown that humans have been influencing the planet's ecosystems for thousands of years, many consider the sudden spike in radioactive carbon caused by the testing of nuclear weapons in 1950s and 1960s the mark of humanity's newly dominant role as chief driver of climatic change.

Now, scientists have found direct evidence of that golden spike in a lone tree, a Sitka spruce found on Campbell Island, which lies in the middle of the South Ocean. The spruce is called the loneliest tree in the world because the next nearest tree lies 125 miles away in the Aukland islands.

"The impact that humanity's nuclear weapons testing has had on the Earth's atmosphere provides a global signal that unambiguously demonstrates that humans have become the major agent of change on the planet," Christopher Fogwill, a professor of glaciology and palaeoclimatology at Keele University, said in a news release. "This is an important, yet worrying finding."

"The global atomic bomb signal, captured in the annual rings of this invasive tree species, represents a line in the sand, after which our collective actions have stamped an indelible mark, which will define this new geological epoch for generations to come," Fogwill said.

Researchers all over the world are largely in agreement that a new epoch has arrived, one marked by human's influence on the climate and environment -- evidenced by rising temperatures, shrinking ice sheets and the spread of manmade materials, like plastics, throughout the planet's ecosystems.

But until now, scientists didn't have an agreed upon universal signal marking the epoch's beginning -- a signal consistent and detectable throughout the geologic record.

The Sitka spruce is native to the West Coast of the United States. But in 1901, the governor of New Zealand planted the tree on Campbell Island. The 100-year-old tree has grown more than 32 feet tall, but it has yet to yield cones, remaining in a permanent juvenile state.

"It seems somehow apt that this extraordinary tree, planted far from its normal habitat by humans has also become a marker for the changes we have made to the planet, it is yet further evidence, if that was needed, that in this new epoch no part of our planet remains untouched by humans," said researcher Mark Maslin, from the University College London.

The researchers described the unique tree and its proof of the newest epoch in the journal Scientific Reports.</s>The planet entered a new geological epoch known as the Anthropocene in 1965, according to new research.

The Anthropocene has become a term used by scientists all over the world, seeking to put a marker on when humans began to leave a significant impact on the planet.

Until now there has been no definitive 'global' signal to enable scientists to officially declare a new epoch.

Now researchers have found the signal for the change by using the accumulation of radiocarbon in tree wood from nuclear bomb tests.

The study, led by UCL and University of New South Wales alongside members of the Australasian Antarctic Expedition 2013-2014, provides the first precise global signal for the Anthropocene from the Southern Hemisphere.

The researchers were able to mark the new epoch due to a radiocarbon peak or 'golden spike' found in the heartwood of a strange and singular tree, a Sitka Spruce found on Campbell Island, a World Heritage site in the middle of the Southern Ocean.

The spruce is locally referred to as 'the loneliest tree in the world' with the next closest tree over 125 miles (200km) away on the Auckland Islands.

The golden spike was created by the culmination of mostly Northern Hemisphere atmospheric thermonuclear bomb tests in the 1950s and 1960s.

The signal was fixed in the wood of the Campbell Island Sitka spruce by photosynthesis.

'We were incredibly excited to find this signal in the Southern Hemisphere on a remote island, because for the first time it gave us a well-defined global signature for a new geological epoch that could be preserved in the geological record,' said lead author Professor Chris Turney from the University of New South Wales.

'Thousands of years from now this golden spike should still stand as a detectable marker for the transformation of the Earth by humankind,' added Professor Turney.

In the Northern Hemisphere, the atmospheric radiocarbon peak occurred in 1964 where the signal is preserved in European trees.

That same peak took until late 1965 (October – December) to reach the Southern Hemisphere atmosphere.

With that spruce, the signal became global, precise and detectable in the geological record, meaning it fitted the requirements as a marker for a new epoch.

The 100-year-old tree itself is an anomaly in the Southern Ocean.

WHAT IS THE ANTHROPOCENE? The Anthropocene is the name of a proposed geological epoch that may soon enter the official Geologic Time Scale. It refers to a time in which human permanently changed the planet. According to the International Union of Geological Sciences (IUGS), we are officially in the Holocene epoch, which began 11,700 years ago after the last major ice age. Some experts argue we should now change the name to 'Anthropocene'. This is from from anthropo, for 'man,' and cene, for 'new'. But up until now, experts have been divided on when mankind caused a lasting impact on the Earth's geology with some suggesting 1964 when the fallout from atomic testing became apparent.

It is naturally found along the North American Pacific Coast but it is credited with being planted on Campbell Island by the Governor of New Zealand in 1901.

The oceanic climate has had an unusual effect on the spruce.

Although it has grown to 33 feet (10m) tall, the tree has never produced cones, suggesting it has remained in a permanently juvenile state.

'It seems somehow apt that this extraordinary tree, planted far from its normal habitat by humans has also become a marker for the changes we have made to the planet,' said co-author Professor Mark Maslin at UCL.

'It is yet further evidence, if that was needed, that in this new epoch no part of our planet remains untouched by humans,' added Professor Maslin.

The study was published in Scientific Reports.</s>The so-called loneliest tree in the world is helping to reveal when exactly humans began to shape our planet’s climate.

In one of the most remote parts of the world, a single tree is helping to shed light on the answer to a single question: what year marks the ‘golden spike’ of the latest human era, referred to as the Anthropocene epoch?

This period of time is considered a massive acceleration not only in the technological development we have experienced, but in what effect we have had on the planet as a whole.

According to the BBC, because of the isolation and location of this Sitka spruce tree in Campbell Island, New Zealand, on the southern hemisphere away from much human activity, it can help find the golden spike that indicates when this era started.

This history of the tree is interesting in itself because it is most definitely not native to the region, having been planted there in 1905, possibly as the starting point of a whole new plantation, and it is now the only tree in an area spanning 200km.

In a paper published to Scientific Reports, the research team led by the University of New South Wales, Australia, found that a drilled core sample of the tree showed a doubling of the amount of carbon-14 in an area of the ring identified as being around in 1965.

The reason for this sudden spike in the radioactive isotope is no coincidence because it marks an important moment in the era of nuclear weapon testing during the Cold War between the US and the former Soviet Union.

Two years after the signing of a ban on atmospheric nuclear testing, the rings show it was too late to prevent the global spread of radioactive fallout.

This isotope would have eventually entered the tree through carbon dioxide absorbed as part of photosynthesis, leaving its legacy deep within its trunk.

“If you want to represent the Anthropocene with the start of ‘The Great Acceleration’, then this is the perfect record to define it,” said Mark Maslin, a co-author of the paper from University College London, who also worked on the project.

“And what’s really nice is that we planted a tree where it shouldn’t be, which has then given us this beautiful record of what we’ve done to the planet.”

With this new data, the international geological community will spend some time to decide on how best to update the timeline of human history portrayed by the Chronostratigraphic Chart.

Once updated, it will become the newest period in human history after the 11,700-year-old Holocene era.</s>When humans first set foot on the moon in 1969, the people of that decade thought the world had changed forever. Little did they know the world had already laid down the precise marker of a far greater global change four years earlier, signalling our planet had entered an entirely new geological epoch, a time period defined by evidence in rock layers, the Anthropocene.

That new epoch began between October and December 1965 according to new research published today in Scientific Reports by members of the Australasian Antarctic Expedition 2013-2014, which was co-led by co-author Professor Christopher Fogwill from Keele University.

The researchers were able to mark this profound change so precisely because of a "golden spike" found in the heartwood of a strange and singular tree, a Sitka Spruce found on Campbell Island, a World Heritage site in the middle of the Southern Ocean. The spruce is locally referred to as 'the loneliest tree in the world' with the next closest tree over 200km away on the Auckland Islands.

The radioactive carbon spike was created by the culmination of mostly Northern Hemisphere atmospheric thermonuclear bomb tests in the 1950s and 1960s. The signal was fixed in the wood of the Campbell Island Sitka spruce by photosynthesis.

Professor Fogwill, Head of the School of Geography, Geology and the Environment at Keele University, said: "The impact that humanity's nuclear weapons testing has had on the Earth's atmosphere provides a global signal that unambiguously demonstrates that humans have become the major agent of change on the planet. This is an important, yet worrying finding. The global atomic bomb signal, captured in the annual rings of this invasive tree species, represents a line in the sand, after which our collective actions have stamped an indelible mark, which will define this new geological epoch for generations to come."

Various researchers from around the world have been talking about declaring a new geological epoch called the Anthropocene, indicating the point where human influence on the planet fundamentally changed the natural world. However, for a new epoch to be officially declared there must be a clear and precise "global" signal that can be detected in the geological forming materials of the future. This radiocarbon spike is that signal.

Lead author Professor Chris Turney, from University of New South Wales, said: "We were incredibly excited to find this signal in the Southern Hemisphere on a remote island, because for the first time it gave us a well defined global signature for a new geological epoch that could be preserved in the geological record. Thousands of years from now this golden spike should still stand as a detectable marker for the transformation of the Earth by humankind."

In the Northern Hemisphere, the atmospheric radiocarbon peak occurred in 1964 where the signal is preserved in European trees. That same peak took until late 1965 to reach the Southern Hemisphere atmosphere. With that, the signal became global, precise and detectable in the geological record, meaning it fitted the requirements as a marker for a new epoch.

The 100-year-old tree itself is an anomaly in the Southern Ocean. It is naturally found along the North American Pacific Coast but it is credited with being planted on Campbell Island by the Governor of New Zealand in 1901. The oceanic climate has had an unusual effect on the spruce. Although it has grown to 10m tall, the tree has never produced cones, suggesting it has remained in a permanently juvenile state.

Co-author Professor Mark Maslin, from University College London, said: "It seems somehow apt that this extraordinary tree, planted far from its normal habitat by humans has also become a marker for the changes we have made to the planet, it is yet further evidence, if that was needed, that in this new epoch no part of our planet remains untouched by humans."

Explore further: Scientists home in on a potential Anthropocene 'golden spike'</s>Researchers have pinpointed the moment that humanity fundamentally changed our natural world – the beginning of a new epoch.

The Anthropocene age began between October and December of 1965, according to a study published in Scientific Reports, which found the marker of this new era in the heartwood of a strange and lonely tree on an island in the middle of the Southern Ocean.

"We were incredibly excited to find this signal in the Southern Hemisphere on a remote island, because for the first time it gave us a well-defined global signature for a new geological epoch that could be preserved in the geological record.

“Thousands of years from now this golden spike should still stand as a detectable marker for the transformation of the Earth by humankind," said lead author Chris Turney of the University of New South Wales, in a statement.

The golden spike is a radioactive carbon spike created by the culmination of atmospheric thermonuclear bomb tests in the 1950s and 60s that appears through photosynthesis in a ring of the spruce tree known locally as the “loneliest tree in the world”. The next closest tree is over 200km away on the Auckland Islands, while this one is by itself on the World Heritage site of Campbell Island.

For some time, geologists have been talking about declaring a new epoch in the history of the world dated from the time at which humanity’s influence started to change the natural order of our planet. But there was no way to pinpoint when the age should start until now.

"The impact that humanity's nuclear weapons testing has had on the Earth's atmosphere provides a global signal that unambiguously demonstrates that humans have become the major agent of change on the planet. This is an important, yet worrying finding,” said Christopher Fogwill, head of the School of Geography, Geology and the Environment at Keele University.</s>A study carried out by University College London and the University of New South Wales in Australia has determined that the Earth has entered a new phase of its geological history, one shaped by the actions of humanity. Called the "Anthropocene," this new age of geologic time, according to the authors of the study published in Science Reports Magazine, to have begun in 1965.

Researchers employed a number of methods to establish that humanity had begun to leave traces of its activity in the geological record, the so-called "Golden Spike." While it has been difficult for scientists to agree on an exact starting point for the Golden Spike, it is generally agreed to have occurred after the Second World War due to the unprecedented expansion of the global economy and the production to never-before-seen levels of plastics and other non-biodegradable products.

The report itself is based on information gathered by the Australasian Antarctic Expedition which took place in 2013 and 2014.

READ MORE: It's Not Just Global Warming, Folks, as Humanity Enters New Anthropocene Epoch

Scientists looking for the definitive point in time at which the human impact on the planet became truly global have focussed their attention on what has been dubbed the "loneliest tree on earth," the Sitka Spruce on Campbell Island some 200km south of New Zealand. The tree contains the residue of nuclear weapons tests carried out in the 1950s and ‘60s.

​"We're putting this forward as a serious contender to mark the start of the Anthropocene. It's got to be something that reflects a global signal," Professor Chris Turney said in a statement to the BBC.</s>A remote spruce planted on Campbell Island in the Southern Ocean holds a defining record of humans, scientists argue. Chris Turney, from the University of New South Wales, Australia, and colleagues, say the tree's wood contains a sharp peak in radiocarbon, and could therefore be used to define the onset of a new geological age known as the Anthropocene Epoch. Prof Turney has been speaking to our science correspondent Jonathan Amos.</s>A remote spruce planted on Campbell Island in the Southern Ocean holds a defining record of humans, scientists argue. The tree's wood contains a sharp peak in radiocarbon, the result of the A-bomb tests in the 1950s and 1960s. As such, it could be used to define the onset of a new geological age known as the Anthropocene Epoch. In this video, Dr Jonathan Palmer from the University of New South Wales, extracts a core from the spruce.
In a Scientific Reports publication, researchers propose 1965 as the start of the Anthropocene era. In that year, human nuclear weapons testing caused a noticeable spike in radiocarbon in the heartwood of the world's remotest tree, a Sitka spruce on Campbell Island, New Zealand. The general scientific community has already been using 1950 as the year "Before Present", when nuclear weapons began to significantly affect the reliability of radiocarbon dating of objects whose organic matter content formed after that epoch.