I have been watching some tennis on the television this past fortnight. The
Australian Open, held in Melbourne as it usually is at this time of the year,
reached a climax last weekend. The stars were on-show and thankfully, for the
finals, the players, match officials, ball boys and girls were joined by a
reasonable number of fans (in this COVID-19 era) in the first “Grand Slam” tennis event of the
year.
The Rod Laver Arena in Melbourne, where the finals are held annually, owes
its name, and pays tribute to, Australia’s most decorated tennis son who played
his game with a strong left hand and won eleven Grand Slam titles. Most
incredibly, Rod Laver is the only male player to have won a calendar Grand Slam
(i.e. winning the Australian Open, the French Open, Wimbledon and the US Open
all in a calendar year) twice. An icon and truly a superstar from an era gone
by.
The Joker
On the court today, as I watched the men’s final of the Open, was one of my
favourite players, Novak Djokovic, currently ranked as world no. 1 by the
Association of Tennis Professionals. Affectionately called “The Joker” because
of his impersonations of his fellow tennis professionals, Djokovic is a Serb and it was this thought that flashed through my mind as I watched him dispatch
Daniel Medvedev, the colourful Russian, in three sets without much ado. He made
the whole affair look easy through courtcraft, mental focus and the flawless
execution of his sublime skills, the result of dedicated practice, discipline
and probably, divine gifting.
The Climatologist from the Danube
The Republic of Serbia has produced several talented sportsmen and women, but
apart from Djokovic, none of them were on my mind this week. Instead my own
focus has been on the work of Milutin Milanković, sometimes anglicised as Milankovitch, who was born
in 1879 (and died in 1958). Like Djokovic, Milankovitch was also a Serb and
extremely talented in his own field. If one wishes to understand why so many,
including Bill Gates, Joe Biden, Al Gore, and Elon Musk, have been mobilized to
address the issue of climate change, then look no further than this mathematician, astronomer, geophysicist, civil engineer and scientist. But above
all, an early pioneering climatologist. It is his work that is the starting
point of any discussion on the subject of the human impact on climate change.
Milutin Milanković - Scientist, Engineer and Climatologist |
Milankovitch was born in the village of Dali, a settlement on the banks of that
famous River Danube, quantitatively, the second longest river in Europe (after
the Volga) but qualitatively, the serene, flowing source of inspiration for some
of the most prominent musical compositions of Strauss, Beethoven and Mozart.
At the age of seventeen Milankovitch moved
to Vienna and six years later, in 1902, graduated as a Civil Engineer. It was
not too long before his contributions started emerging in this field as he built
dams, bridges, viaducts, aqueducts and other impressive structures, using reinforced
concrete, throughout the region of Austria-Hungary. As a Civil Engineer, he was
responsible for at least six patents in the field of reinforced concrete and as
his reputation in his chosen profession soared, so did his abundant financial
wealth.
Milankovitch continued to practice civil engineering in Vienna until 1
October 1909 when he was offered the Chair of Applied Mathematics at the
University of Belgrade. Though he continued to pursue his investigations of
various problems pertaining to the application of reinforced concrete, he
decided to concentrate on fundamental research.
In the construction of his
concrete based structures, Milankovitch was required to understand an area of
science called meteorology, in particular the forecasting of weather. When
studying this subject, he was introduced to the work of the contemporaneous
climatologist, Julius von Hann. Known today as the “Father of Modern
Meteorology”, von Hann was an Austrian who, in his works, discussed (but was
unable to explain) the cold periods or “mystery ice ages” that had occurred in
the Earth’s history.
The Mystery of the Erratics
The root of this mystery lay in the presence of “erratics” - boulders of a material composition that was inconsistent with the geology
found around them – in certain parts of Europe. It was believed that these
erratics were deposited by glaciers. What made these erratics a mystery was the
fact that there were no existing glaciers in close proximity to these isolated
erratics. As erratics were generally expected to be found in the path of
glaciers, the absence of glaciers in the vicinity of some erratics, soon led to
the hypothesis that the climate of Earth had been far different in the past.
Milankovitch set about applying his mind to solving this mystery.
Before long,
he advanced predictions on the climates of all the resident planets of the Solar
System. This was ground-breaking work for the times but his second contribution
was even more impactful. Milankovitch examined how variations in three types of
Earth orbital movements affect how much solar radiation (known as insolation)
arrives at the top of the Earth’s atmosphere. He also calculated where exactly
this insolation reaches.
The Milankovitch Cycles
These cyclical orbital movements, which collectively became known as
the Milankovitch Cycles, cause variations of up to 25 percent in the amount of
incoming insolation at Earth’s mid-latitudes (the areas of our planet located
between about 30 and 60 degrees north and south of the equator) and thus impact
average temperatures that are experienced.
The Milankovitch Cycles take into account:
•
the shape of Earth’s orbit, known as its eccentricity resulting in summers in the northern hemisphere being 4.66 days longer than the winter and spring bein 2.99 days longer than autumn;
• the angle Earth’s axis
is tilted with respect to Earth’s orbital plane, known as obliquity; and
• the
direction Earth’s axis of rotation is pointed, known as precession.
The small
changes set in motion by the Milankovitch Cycles act independently but together,
influence Earth’s climate over very long timespans, leading to larger changes in
our climate over tens of thousands to hundreds of thousands of years.
Milankovitch combined his understanding of the Cycles to create a comprehensive
mathematical model for calculating differences in solar radiation at various
latitudes of the Earth along with the corresponding surface temperatures. His
model was like a Climate Clock or Time Machine, not solely able to predict future
weather patterns but which could also be regressed to provide a picture of the
Earth’s climate at various points in its history over many eons.
Milankovitch
calculated that Ice Ages occur approximately every 41,000 years. Subsequent
research confirmed that they did occur at these 41,000-year intervals between one and
three million years ago. But there are some (as of yet) unexplained constraints and exceptions.
As an example, about 800,000 years ago, the cycle of the Ice Ages lengthened to
100,000 years, matching Earth’s eccentricity cycle. Whilst various theories have
been proposed to explain this change, scientists do not yet have a clear answer
as to why this transition occurred.
Milankovitch’s work was supported by other
researchers of his time, and he authored numerous publications on his
hypothesis. But it was not until about 10 years after his death (in 1958) that
the global science community began to take serious notice of his theory.
Validation of Milankovitch's Theory
In
1976, a study in the journal Science by Hays et al., using deep-sea sediment
cores, found that the Milankovitch Cycles correspond with periods of major climate
change over the past 450,000 years, with Ice Ages occurring when the Earth was
undergoing different stages of orbital variation. Several other projects and
studies also upheld the validity of Milankovitch’s work, including research
using data from ice cores in Greenland and Antarctica that provided strong
evidence of Milankovitch Cycles going back many hundreds of thousands of years.
In addition, his work was embraced by the National Research Council of the U.S.
National Academy of Sciences.
Whilst scientific research is a continuous
process, Milankovitch’s work had moved from conjecture to hypothesis and is today classified as accepted theory that predicts the timing of glacial-
interglacial cycles.
So, what do Bill Gates, Joe Biden, Al Gore, Elon Musk and
many others have to do with the presence of erratics, orbital cycles and the
findings of Milankovitch? What has been the cause of all the recent hullabaloo?
The Evidence for Climate Change
Well, per the theory of the Milankovitch Cycles,
the Earth should be naturally cooling, with average temperatures reducing at
this time in our astronomical history. Glaciers should also be advancing
(accumulating more snow and ice than it melts or calves). But empirically, what
is being observed is contrary to the theoretical predictions (which are supported
by eons of historical data). Instead of the Earth cooling, average temperatures
are increasing, and glaciers, are retreating (more snow and ice melting rather
than accumulating).
The Callendar Effect
This observed anomaly suggested that either the theory
of the Milankovitch Cycles required review or something else was impacting the
long-term trends of global temperatures. In 1938, Guy Stewart Callendar, an
English engineer (who was born in Canada), first postulated that the astronomical
related foundations of the Milankovitch Cycles were reliable but it was the
increasing levels of carbon dioxide concentrations in the atmosphere that were
leading to an increase in global temperatures. Over the subsequent decades, his
theory has been demonstrated to be accurate and has since been christened the
Callendar Effect.
Callendar showed that in the 50 years prior to 1938, average
global temperatures were increasing in tandem with carbon dioxide concentrations
in the atmosphere. Initially he thought this to be a positive development,
postponing the advent of another Ice Age, but over the next several decades,
complex computer models revealed that uncontrolled levels of carbon dioxide
emissions would cause irrevocable damage to the environment of the Pale Blue Dot
that is Earth, our collective home.
The Carbon Culprit
Once carbon dioxide was identified as one of the primary
culprits of global temperature increase, it then became imperative to identify
the sources of the production of this gas so that real reductions could be made
in its use. The finding is that it is our lifestyles and expectations that are
changing the trajectory of the evolution of Earth. The growing global population
is demanding more energy to live in greater comfort and to perform industrial
work activities more efficiently. It is also no secret that human longevity has
increased in tandem with carbon dioxide emissions. The paradox is that in
emitting more carbon dioxide today, we increase our immediate personal longevity
but we also erode the possibilities for those who will follow us as the future
custodians of Earth.
In the long term, our actions or inaction today may
threaten the very existence of humankind itself.
Paris, 2015
On 12
December 2015, a legally binding international treaty on climate change,
involving 196 countries was adopted. It came into force on 4th November 2016 and
is called the Paris Agreement. Its vision is to limit global warming to well
below 2 degrees Celsius compared to pre-industrial (1750s) levels.
There are
many strategies that cascade from the pursuit of this planet-wide mission, but
one obvious common feature does seem to repeat itself. The fact is that the less
we rely on carbon and the more we harness the five major renewable energy
sources: i.e.:
• Solar energy from the sun;
• Geothermal energy from heat inside
the earth;
• Wind energy;
• Biomass from plants; and
• Hydropower from flowing
water;
the greater our chances of delivering on the goals of the Paris
Agreement and the greater our chances of survival as a species.
Cometh the Hour, Cometh the Inventor
Irrespective of the source of renewable energy, the method of transmission of
the renewable forms of energy from its source to its user will likely be
electrical. Enter then, probably one of the greatest inventors the world has
known, Nikola Tesla, a Serbian-American inventor, engineer and futurist. Sometimes called, “the genius who lit the world”, Tesla is well known for the
Tesla coil (which laid the foundation for wireless technologies), the
development of the alternating-current electrical system, while also being
credited with the discovery of the rotating magnetic field.
In the coming
decades, Tesla’s discovery of the alternating current electrical system will
become increasingly critical for delivering clean energy to users the world
over. It is reported that Tesla never really cared about money, repeatedly
saying that what he wanted most was to provide free electricity to the world.
His wish may yet be granted as renewable energy sources come to the fore.
Tesla Incorporated
To close this post, I would like to relate this story about the other Tesla that
is making the headlines these days. The Tesla motor vehicle is synonymous with
the name of Elon Musk. The reality is somewhat different. Elon Musk did not have
a say in the naming of Tesla Incorporated as he joined it only after it had been
formed. Tesla’s name was actually thought up in Disneyland’s Blue Bayou
restaurant, when Tesla Inc.’s co-founder, Martin Eberhard, pitched it to his
then girlfriend (and now wife), Carolyn.
Martin Eberhard chose the name, after
months of unsuccessful pitches, to honour Nikola Tesla, the Serbian-American
inventor who created the AC electric motor that is used in Tesla’s cars.
Perhaps, when we next see a Tesla motorcar and we wonder what we could do to make the
world a cleaner and healthier place, we should remember the words of Nikola
Tesla:
“I alone cannot change the world, but I can cast a stone across the water to
create many ripples"
Please note that all stamps and the First Day Cover used in this post are from my personal collection.