Climate Change For Dummies. Elizabeth MayЧитать онлайн книгу.
coal and oil was burned, humans got to use that ancient solar energy again to make things and move things and keep things warm. And all that carbon was released again, off into atmosphere as carbon dioxide and other gases called greenhouse gases because they act like the glass in a greenhouse to keep heat in. So, like any good greenhouse, the Earth became warmer. And it’s still getting warmer today. And that’s the problem to solve.
Tapping into The Roots of Global Warming
Just what are humans doing to release all those GHGs into the atmosphere? You can pin the blame on two main offenses, which we discuss in the following sections: burning fossil fuels and deforestation.
Fueling global warming
When you burn fossil fuels, such as coal and oil (named fossil fuels because they’re composed of ancient plant and animal material), they release vast amounts of GHGs (largely, but not exclusively, carbon dioxide), which trap heat in the atmosphere. Fossil fuels are also a limited resource — meaning that humanity can’t count on them over the long term because eventually they’ll just run out.
The fossil fuel that produces the most GHG emissions is coal, and burning coal to produce electricity is the major source of coal-related GHGs. The second-worst offender is using gasoline and diesel for transportation, followed by burning oil to generate heat and electricity. In fact, if people could replace the coal-fired power plants around the world and switch away from the internal combustion engine, humanity would have most of the problem licked. This switch is happening now, more and more quickly, but industries that have been built on the fossil fuel bonanza, and their supportive governments and bankers, continue to delay the inevitable progress. (Check out Chapter 4 for more fossil fuel info, Chapter 13 for the scoop on energy alternatives, and Chapter 17 for an introduction to the disruption expected and feared by those industries.)
Heating up over deforestation
Forests, conserved land, and natural habitats aren’t important just for the sake of saving trees and animals. Forests and all greenery are important players in keeping the climate in check. Plants take in the carbon that’s in the atmosphere and give back oxygen, and older trees hold on to that carbon, storing it for the duration of their lives. By taking in carbon dioxide, they’re significantly reducing the greenhouse effect. (See Chapter 2 for more about how plants help the Earth keep atmospheric carbon at a reasonable level.)
Unfortunately, much of the world’s forests have been cut down to make way for farmland, highways, and cities. Deforestation is responsible for about a quarter of GHG emissions. Rainforests and mangrove forests (very productive forests that grow in wetlands) are especially good at soaking up carbon dioxide because they breathe all year round. Temperate forests, on the other hand, don’t absorb much carbon dioxide over the winter, practically going into hibernation. (Chapter 5 has more about deforestation.)
Examining the Effects of Global Warming around the World
This book could easily be called Climate Emergency For Dummies. Although “global warming” is the common term for the climate changes that the planet’s experiencing (and scientists agree that average global temperature is increasing with the buildup of GHGs), the term doesn’t tell the whole story. The Earth’s average surface temperature is certainly going up. But while the average keeps rising, the variations around the average are also getting larger and larger. So some areas of the planet may actually get colder or experience more extreme bouts of rain, snow, or ice build-up. Consequently, most scientists prefer the term “climate change.” In the following sections, we look at how different places around the world will experience climate change.
Of course, different parts of Earth have very different climates now, and climate change won’t affect every part of the planet in the same way. The following sections explain in general terms how some parts of the world are being affected by climate change.
The United States and Canada
In the United States and Canada, average temperatures have been rising because of climate change. As a result, the growing season has lengthened; trees have been sucking in more carbon, and for a while, farms were more productive. The recent years have had far more severe wet years followed by extreme drought. The 2021 drought had negative and long-term impact on wheat, corn, and other crops, according to Forbes.
Many plants and animals are spreading farther north to adapt to climate changes, affecting the existing species in the areas to which they’re moving. Increased temperatures have already been a factor in more forest fires and wildfires and damage by forest insects, such as the pine beetle epidemic in the interior of British Columbia, Canada. (See Chapter 8 for more information about how global warming will affect animals and forests.)
Scientists project that the United States and Canada will feel the effects of climate change more adversely in the coming years. Here are some of the problems, anticipated to only get worse if civilization doesn’t dramatically reduce GHG emissions:
Droughts and heat domes: Rising temperatures are increasing droughts in areas that are already arid, putting even larger pressure on scarce water sources in areas such as the U.S. Southwest. In Canada, 600 people died from extreme heat in 2021 as a heat dome (happens when the atmosphere traps hot ocean air) formed over the west and drove temperatures to record levels. Some areas of British Columbia experienced temperatures of 122 degrees Fahrenheit (50 degrees Celsius).
Evaporating lakes: The cities in the great heartland of the Great Lakes Basin will face retreating shorelines when the water levels of the Great Lakes drop because of increased evaporation. Lower water levels will also affect ship and barge traffic along the Mississippi, St. Lawrence, and other major rivers.
Floods: Warmer air contains more moisture, and North Americans are already experiencing more sudden deluge events, causing washed out roads and bridges, and flooded basements and even Manhattan’s subways. In British Columbia in 2021, a form of rainstorm so extreme it’s called an atmospheric river caused massive flooding. The estimated damage to farms and transportation infrastructure was about $5.9 billion US, $7.5 billion Canadian. Bridges and other sections of roads and highways were washed away, isolating coastal areas from the rest of Canada for weeks.
Major storms: Warming oceans increase the risk of extreme weather that will plague coastal cities. Think of Hurricane Katrina, arguably the most devastating weather event ever to hit a North American city, as a precursor of storms like Superstorm Sandy. Katrina was whipped into a hurricane with a massive punch from the super-heated waters of the Gulf of Mexico in 2005. In 2021 a devastating series of tornadoes, way outside the “normal” tornado season, clobbered the southern and central United States, killing almost 100 people and causing millions in damage. Not all extreme weather events are hurricanes. Global warming is expected to increase ice storms in some areas and thunderstorms in others.
Melting