Potential environmental crises worse than global warming

Worse than global warming

For those of us who work in the field of climate change, it is some consolation to take a break and reflect there are crises worse than global warming.

Giant meteor: Sixty-six million years ago, a meteor impact triggered an extinction event that killed most of the dinosaurs. When the meteor hit, it was a double whammy. First, rock fragments triggered fires as far away as 2000 kilometres from the site. Those fires put carbon dioxide, methane and carbon monoxide into the air. Then the impact itself put microdust into the air, blocking sunlight and cooling the planet drastically. Winter-like conditions lasted for two full years and long-term effects lowered average temperatures by as much as 15 C over the next 15 years. Less sunlight means less plant life, which means less available food. Scientists estimate 75% of species went extinct. Don’t worry, a rock that size only hits Earth every 100 million years or so.

Death of the Sun: The Sun, our beloved yellow dwarf star, is critical to life on earth. Five billion years from now the sun will begin to run out of fuel. Currently it burns hydrogen, turning it into helium. When the supply of hydrogen gets low, it will start to burn helium creating carbon. Fusing helium creates much more heat and this heat will cause the outer layer of the star to puff up and get much larger. Our sun will expand, becoming a red giant, swallowing up Mercury, Venus, and Earth in the process.

Supervolcanos: Earthquakes have the Richter scale and volcanoes are measured by the “Volcanic Explosivity Index” (VEI). Vesuvius had a VEI of five and Kracatoa was a six, to name some familiar eruptions. During April 1815, Mount Tambora in Indonesia erupted, with a maximum VEI of seven on April 10. Approximately 10,000 people were killed as a direct result of the explosion. A further 50,000 in the vicinity of the explosion died of hunger and disease. However, the biggest impact came from worldwide changes in the weather. The year 1816 is known as “the year without a summer.” Many compounds (such as methane, carbon dioxide and water) increase the atmospheric greenhouse effect, making the earth warmer. However volcanoes release sulfur (in the form of sulfur dioxide and hydrogen sulfide) into the air, where it interacts with hydroxide and water to create sulfuric acid aerosols. These fine droplets reduce the Earth’s temperature by increasing the amount of sunlight reflected back into space. In 1816, so much sulfur was released into the atmosphere that the growing season was ruined—lower temperatures (including frost in June, July and August) destroyed crops and the crops that survived didn’t receive enough sunlight to thrive. Weather patterns were altered with some regions experiencing flooding and some drought due to changed monsoon patterns. It’s hard to estimate how many people died due to the world-wide knock on effects. Will this happen again? Yes but probably not soon. Some estimates suggest that VEI-seven explosions occur on the time scale of 200 to 400 years. Volcanoes to watch include Atitlan in Guatemala, Cerro Negro in Chile and Taal in the Philippines.

The Great Oxygenation Event: “The Great Oxygenation Event” took place 2.4 billion years ago during the Paleoproterozoic. Life on earth consisted of single cell organisms which were adapted to a life without oxygen. But then cyanobacteria started to take over. These were the first life forms capable of photosynthesis, (i.e., they could generate energy from sunlight) and photosynthesis took in carbon dioxide and created oxygen. Other life forms found the oxygen to be extremely toxic. It killed off 96% of the existing species. For the cyanobacteria photosynthesis was a powerful advantage and led to multi-celled organisms and eventually to the development of plants and animals. In addition to changing the makeup of the atmosphere, the Great Oxygenation Event changed the climate. The makeup of the atmosphere changed from methane (a strong greenhouse gas) to carbon dioxide (a weaker one) which probably triggered an ice age. It may be the most significant impact on the environment in the history of the planet.

This article is written by or on behalf of an outsourced columnist and does not necessarily reflect the views of Castanet.

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About the Author

Kristy Dyer has worked in the sustainability field for more than 10 years, including work with solar energy in New Mexico and cleantech in Silicon Valley. After she moved to the Okanagan, she ran a small business, Teaspoon Energy, doing energy audits of large houses. Most recently, she worked for a B.C. business doing carbon footprints for tourism organizations.

She has written about sustainability since 2012. You can find her columns archived at TeaspoonEnergy.blogspot.com.

Dyer has a background in physics and astronomy, and has occasionally been caught trying to impersonate an engineer.

A long-time member of First Things First, Penticton’s local climate change group, whose goals are to educate and lobby for solutions to the climate crisis, Dyer is honoured to live, work and play in the unceded, ancestral and traditional territory of the Syilx Okanagan Nation.

You can contact her at [email protected]

The views expressed are strictly those of the author and not necessarily those of Castanet. Castanet does not warrant the contents.

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