Climates Have Always Changed: So What’s Different Now?

Emlyn Koster, PhD

June 2022

Boston Tourism describes the city’s weather as “a tale of uncertainty” and its TimeOut Guide issues 18 reminders of why “New England weather isn't for the weak”! Such commentary revives memories of my early years in England where talk about inclement weather seemed like a social ritual. Frequent forecasts often referred to weather averages or records, but the term climate never came up.

Natural Climate Changes

As a geology student I learned that climate changes over tens and hundreds of millions of years resulted from a combination of changing latitudes and altitudes of land areas, shifting patterns of ocean circulation, and evolutionary developments in the atmosphere. Each imperceptibly slow in human terms, I was also curious about the comparatively fast climatic oscillations and accompanying ecological changes that defined an Ice Age across the Northern Hemisphere that began two and half million years ago.?

During doctoral fieldwork in Yukon’s St. Elias Mountains, I was immersed in a landscape emerging from the immense impacts of glaciation. The same metamorphosis is occurring now across Massachusetts where an icesheet from Canada reached its maximum southeastward extent about 25,000 years ago. By about 15,000 years ago, the Boston area was free of ice which had been as thick as the height of the Hancock Tower. The landscape became a mosaic of erosional and depositional features on which the region’s first humans began to settle over 10,000 years ago.

The Earth System

In 1948, the astronomer Fred Hoyle of Big Bang Theory fame anticipated that “once a photo of the Earth is taken from the outside, new ideas as important as any in history will be let loose”. Hoyle’s prediction came true, well kind of, two decades later with iconic Earth and Earth-rise photos from NASA’s lunar missions. Labeled a breakthrough for the USA in its space race with the USSR, I think those haunting images rank as the most profound contribution of the Apollo program. Mirroring what many early astronauts termed ‘the overview effect’ to describe their shift in consciousness towards care for the planet, much of the world soon witnessed the Earth’s blue-green beauty, wafer-thin atmospheric envelope, and lonely fragility. The Independent newspaper in the UK recently reported that the photos “would eventually launch a thousand environmental movements”, most significantly as annual Earth Days which according to their umbrella network now occur in over 170 countries as the “the largest secular civic event in the world”.?

Thwarting what should have been the full dividends of that breakthrough were the “two solitudes” of the sciences and the humanities as warned in 1959 by novelist and chemist C.P. Snow. In 1962 the acclaimed book ‘Silent Spring’ introduced the world to Rachel Carson, a courageous field biologist, who urged: “The more clearly we can focus our attention on the wonders and realities of the universe about us, the less taste we shall have for destruction”. Already in their 1970s Gaia approach, biologists James Lovelock and Lynn Margulis regarded the Earth as one interlocked ecosystem with concentric envelopes – the atmosphere, hydrosphere, cryosphere, biosphere, and lithosphere – each with self-regulating physical, chemical and biological processes. Interdependency of these envelopes means that no local change remains an isolated development.

Existential Climate Changes

A 1953 Scientific American article by the renowned climatologist Helmut Landsberg reported: “The big question on Earth is the influence of human activity on the atmosphere... There is some evidence that industrial life has increased the amount of carbon dioxide in the air”. It took almost the next half century to amass and begin to publicize evidence for human-caused climate change. In 2019, Dictionary.com announced ‘existential’ as a new word of the year for a new and pervasive “sense of grappling with the survival – literally and figuratively – of our planet, our loved ones, our ways of life”. In 2020, climate change joined the Covid-19 pandemic, ethno-racial violence, and the rise of supremacist regimes as widely reported existential crises.?

The UN’s Paris Agreement in 2016 thrust 1.5° Celsius, equivalent to 2.7° Fahrenheit, into worldwide attention. Last fall’s UN climate conference in Glasgow intensified the search for global ways to cap atmospheric warming to this increase from the pre-Industrial Age average. The difference seems inconsequential, for example, in relation to Boston’s average January and July temperatures of 78°F and 46°F, let alone to southeast Massachusetts records of 107°F in 1975 and -35°F in 1981. But more than ever, it is crucial for the public to grasp that regional climate is the average of local weather over at least three decades and that climate is sensitive to very small changes in average temperature. On June 1?The Boston Globe?reported on a new University of Massachusetts scientific study: “By the end of the century, average temperatures in the Boston area could increase as much as 10 degrees above 2000 levels, while seas could rise more than 10 feet, under the worst circumstances. Over the same period, intense precipitation could increase by 30 percent and flooding from swollen rivers could surge by 70 percent.” Only time will tell.?

Meanwhile, Athens is the world’s first city to appoint a Heat Officer. Her recent TED Talk noted that the previous summer’s heat dome in British Columbia was almost 5°C (9°F) more intense than a recent one in Greece. It is increasingly common that weather updates combine with news of devastating heatwaves, record floods, prolonged droughts, forest fires, tornado swarms, and the exacerbating role of climate change in the pandemic. Last August, a first-of-its-kind study by UNICEF found that “nearly half of the world’s 2.2 billion children are at extremely high risk of the impacts of climate change”. Our planet’s mounting’s perils have become undeniable.

Interest to Activism

As an undergraduate geologist I took an elective geography course titled ‘Weather and Climate’: it focused on the structure of the atmosphere and climate zones between the equator and poles. There was no mention of the now-familiar terms ‘extreme weather’ and ‘climate change’.??

Tracking the weather is habitual: we want to know what will be comfortable to wear, about any impending storms, and the forecast for an upcoming destination. What has changed – and it is a massive shift since my training – is that updates from near and far about extreme weather and climate change are frequent and pessimism about the future has crept into cultural commentaries. Amanda Hess in The New York Times remarked last February: “We once said that we would stop climate change for the benefit of our children, but now we can tell ourselves that our children will take care of it for us.” No wonder that youth, most notably Sweden’s Greta Thunberg, have become activists. Holistic thought and action in whole Earth System terms is what the world urgently requires.

https://www.mos.org/blog/the-earth-around-us/whats-different-now