Climate change—modifications in long-term weather patterns—comes in two flavors. Natural and manmade.
Natural climate change has occurred many times in the long history of the Earth and can take place in as short a time span as 200,000 years or as long a time span as several hundred million years. Manmade climate change has occurred only once in the 4.5-billion-year history of the planet. In fact, it’s happening right now, and though it has taken less than 200 years to get underway, its potential repercussions may affect people and ecosystems around the world as it:
• raises temperatures
• increases the duration, frequency, and intensity of storms
• accelerates the melting of glaciers
• causes declines in such essential crops as wheat and maize
• raises sea levels
• dramatically increases habitat loss, thus propelling many plant and animal species into decline or extinction
• disrupts the marine ecosystem and endangers a significant part of the world’s food supply
• increases ocean acidity
• decreases winter (and perennial) snowpack on mountains through much of the world, resulting in significant reductions in fresh water resources for billions of people
• prolongs and intensifies drought
• increases the frequency, duration, and size of wildfires
• displaces millions of people from islands and low-lying coastal areas
• increases the incidence of malaria, dengue fever and other mosquito-borne diseases
• reduces the amount of water in natural underground aquifers and other groundwater supply points
• increases air pollution
• accelerates and intensifies the Sixth Major Extinction event, currently underway
• increases aridity in already dry areas
This is, of course, only a partial list of the consequences the world faces, and manmade climate change will almost certainly affect different areas of the world in different ways and degrees.
If climate change has happened so often in the past, why will manmade climate change lead to such devastating outcomes? Because of the speed at which it is occurring.
Lets look at one example of natural climate change that has been slowly transforming the ecosystem of central Asia into one of the most arid regions on the planet, change that has been underway for more than 20 million years.
Many periods of climate change in the planet’s history have occurred as the result of a natural increase in carbon dioxide levels, but a different geologic phenomenon caused this particular climate change event—desertification—to unfold in central Asia.
More than 100 million years ago, plate tectonics sent India on a northeasterly collision course with Eurasia. When it crashed into the much larger continent approximately 50 million years ago, the incredible impact of that collision uplifted the coast of Southern Asia from sea level to more than 29,000 feet, forming the Himalayan mountains and the Tibetan plateau in the process and precipitating a climate change event that continues to this day.
Soon after this massive 1,500-mile long mountain range formed, a huge rain shadow formed behind it. Where once the annual monsoon rains could reach the central Asian continent as they had for millenia—supplying it with irrigation for its plant life in the process—now the heavy clouds dropped most of their moisture on the summits and slopes of the Himalayas. With less moisture delivered inland, a natural change in the climate ensued and plant life began to decline. Not rapidly. But persistently over millions of years. Then, aided by the “relatively recent rise of lesser-known mountain ranges, such as the Tian Shan and the Altai,” even less moisture reached central Asia. “As a result,” Adam Hadhazy reports in his recent article in the Stanford Report, “great stretches of what we now consider western China, southwestern Mongolia and eastern Tajikistan became barren earth or laced by sand dunes.” A vast region that once supported plant and animal life became “one of the most arid regions on the planet.”
That’s how natural climate change works. Slowly and inexorably.
Tectonic activity caused India’s collision with Eurasia 50 million years ago. Additional geologic activity caused still further mountain building in the area over the ensuing 25 million years, natural occurrences that eventually choked off virtually all moisture from reaching the central Asian plains, turning a large area of central Asia into a desert. Climate change 50 million years in the making.
In direct contrast, manmade climate change has transpired at breakneck speed. Mankind began using coal, oil, and natural gas well before the modern age. But the Industrial Age ushered in an era of unbridled and escalating fossil fuel usage. As recently as 2012, “coal, natural gas and oil accounted for 87% of the world’s primary energy consumption,” according to an article in Scientific American. And even though the fossil fuel industry apparently knew about the connection between fossil-fuel usage and climate change years before global warming became a hot topic, the industry itself and its champions in government continue to publicly deny the relationship, disregarding the impacts that climate change has on ecosystems around the world and the effects it will have on its children, grandchildren, and all of humanity.
In a mere 150 to 200 years, we have initiated the first era of manmade climate change, resulting in worldwide temperature increases, ocean acidification, polar ice loss, melting glaciers, rising sea levels, and many more climatic effects. The level of carbon dioxide in the atmosphere stands at more than 400 parts per million worldwide—the highest it’s been in 800,000 years. And all reputable scientific research links these record levels to fossil-fuel usage.
We have the means to mitigate the effects of manmade climate change. Do we have the will? Or will we continue to use fossil fuels with reckless abandon?
You can learn more about manmade climate change and its consequences in the following articles:
• Stanford Researchers Capture Central Asia’s ‘De-greening’ Over Millions of Years into a Modern-day Desert
• The Neogene de-greening of Central Asia
• Andes mountains lose nearly half their ice in just 40 years
• The Point of No Return: Climate Change Nightmares Are Already Here
• Historic Shrinking of Antarctic Ice Sheet Linked to CO2 Spike
• Glaciers Getting ‘Thinner and Smaller Faster and Faster,’ Expert Says
• Climate Change Means Moving. Just Don’t Say ‘Retreat.’
• Effects of Global Warming
• 25 Devastating Effects Of Climate Change
• The Consequences of Climate Change
• Zimmerman column: Ocean Acidification – the other CO2 Problem
• The World Reached 3 Dangerous Climate Change Milestones this Summer
• First Time in 800,000 Years: April’s CO2 Levels above 400 ppm
• Fossil Fuel Use Continues to Rise
• Energy Perspectives: Fossil Fuels Dominate U.S. Energy Consumption
• Fossil Fuels
• History of Fossil Fuel Usage since the Industrial Revolution
• When Continents Collide: New twist to 50-million-year-old Tale
• Antarctica Was Home to a Rainforest some 50 million Years Ago
• Paleoclimatology: How Can We Infer Past Climates?
• Rain Shadow