The earth seems like a very large thing to affect, and many people can't get their brain around it. But humans have had very real, documented impact on the earth.
Some of this is copied from VisualWriter.com (another Web site by the author).
While it is sometimes fashionable to denigrate environmentalists for protecting snail darters and trees, historically a small number of people have had major negative impact on the environment.
Gray whale - driven close to extinction by whalers.
Bison (buffalo). At the beginning of the nineteenth century bison herds roamed the west, with a population numbering around thirty million. They provided food and leather for clothes and shelter, for native Americans. By the beginning of the 20th. Century they were near extinction, with only about a thousand remaining. Two factors are believed responsible. Cold temperatures that the bison genetic line was unable to bear, and settlers hunting the bison for sport, and then leaving the carcasses to waste. Many believe that the majority fault was man's actions - hunters with guns. It took only about 50 years for the Southern Plains tribes to be suffering from starvation.
Sea otter. Having a soft, lustrous fur, this mammal was hunted for its fur in the 1800s, and by 1911 was nearly extinct.
Beaver. These animals were plentiful in the North American continent, with Canada alone believed to have had nearly 6 million. When beaver fur became fashionable for hats in Europe, trappers nearly wiped out the creature from the continent by the mid-19th. Century. Fortunately silk hats became all the rage.
Passenger Pigeon. This bird was once the most abundant bird on the planet. Early North American settlers reported flocks that covered the sky for hours. The bird was hunted worldwide for food, and its habitats were cleared. All that has been seen of the Passenger Pigeon since 1900 is pictures in written accounts - it is extinct.
Bees. It has been said that if the bees die, humans die. We depend on them for planting food. There has been great concern over honey bee hive death, and that problem is being addressed, but it is only the tip of the iceberg.
"In a study of 41 different crop systems worldwide, honeybees only increased yield in 14 percent of the crops. Who did all the pollination? Native bees and other insects."
"The bees you should be concerned about are the 3,999 other bee species living in North America, most of which are solitary, stingless, ground-nesting bees you’ve never heard of. Incredible losses in native bee diversity are already happening. 50 percent of Midwestern native bee species disappeared from their historic ranges in the last 100 years. Four of our bumblebee species declined 96 percent in the last 20 years, and three species are believed to already be extinct."
You're Worrying About the Wrong Bees | WIRED
North Atlantic Cod. Have we learned anything since the late 1800s? Even if man wiped out some of the land animals, the vast ocean is still rife with fish, right? Not.
North Atlantic Cod, a deep water ocean fish, has declined 80% in number in 30 years, due to over-fishing. While the impact on our food supply is bad, another food fish in the area similarly declined, plus three other species declined that are not used for food. Recent studies show an 87% decrease in five species in 17 years. These other fish live and feed in the 400 to 1200 meter depth, below where cod are fished. Why?
The nets used for fishing grab everything - and other fish are ground and put into chicken and dog food. What is even worse, the nets used for fishing drag the bottom and destroy the ecosystem there. What was once a major fish supply and ecosystem has been nearly destroyed, and will literally take many generations to revive. Fifteen percent of the world's protein comes from fish. These food fish take about 15 years to raise - a fish farm won't help us with them - it is too inefficient to be economical. For more information, listen to NPR Counting and Improving Fish Populations. Where are we going with this?
The problem is getting worse, not better. Ocean Life Faces Mass Extinction, Broad Study Says
Land. Animals are just one element of ecology. Our land is literally disappearing. The topsoil that we farm for food is a relatively thin layer of the ground, in some places less than an inch or so deep with clay or rock protruding through this layer (as in Southern Indiana, Missouri, and other hilly areas). The ground disappears by erosion. More than 55 percent of this damage is caused by water erosion and nearly 33 percent by wind erosion. Farming makes the ground exposed to heavy erosion. We have to farm to raise food, so there is no answer, right?
Every year soil erosion and other forms of land degradation rob the world of 10 to 15 million acres of farm land. Every year 25,000 million tons of topsoil are washed away, and it is made much worse by the actions of man.
In the 1930s, wind erosion devastated millions of acres of farmland in the US. The Government set up an agricultural extension service to train farmers in soil conservation. To retain soil, they were taught to plow less deeply, and to plant trees, hedges, and grass around the edges of fields. Trees form a natural barrier against wind erosion. Keeping vegetation on the land, and using strips between plots of land, are two ways that wind and water erosion is controlled. Strip farming uses natural barriers, including strips of trees. See: Food and agriculture organization of the United Nations. and Prairie Farm Rehabilitation Administration of Canada.
Have we learned anything? One of the first things that many farming organizations do is remove the trees from the land to get the most production from the land. Every few years I pass by one of my former homes in Northern Indiana. It was a farm with a beautiful tree-lined, wide creek running through it, and pastures on each side. We used to picnic there and fish. My sister once nearly drowned in the creek. I can barely find it now - all of the trees are gone and the creek is a narrow drainage ditch. Tree huggers? Try to find a tree in farming territory.
While our land is disappearing, so does the natural species in the land. When trees are removed, the natural habitat for wildlife is removed, and those flora and fauna species decline and disappear. The ecosystems that they depend on are also the ecosystems that the earth, and we people, depend on.
"Ten percent of all bird species are likely to disappear by the year 2100, and another 15 percent could be on the brink of extinction." This, according to a study by Stanford University biologists, published in the Online Early Edition of the Proceedings of the National Academy of Sciences (PNAS) in December. See the Science Daily article: The Global Bird Populations Face Dramatic Decline In Coming Decades.
Air and global warming. Various factors in the environment are coming to light as scientists learn more about the environmental impact of CO2, and see more things are contributing to it. The tipping point is looking closer and closer, and once we go over the tipping point, the earth will become uninhabitable. What we are seeing in the last 60 years is a sharp spike in CO2 levels, unparalleled in hundreds of thousands of years. Sharp spikes indicate threatening changes.
A February First: CO2 Levels Pass 400 PPM Milestone
There was no pause in global warming. The 20 to 30 year oscillation in the Pacific sent the warm air to Antarctica, where it warmed it and accelerated melting. When Arctic temperatures were added to the global figures, global warming was right on track.
Sorry, Climate Change Deniers: Warming Not “Paused” and Modeling Not Flawed
The Arctic is suffering more than we thought. "The enormous mass of ice sitting on the Antarctic bedrock — "grounded ice" — is to a large extent held back from the ocean by those shrinking ice shelves. "They're stopping that grounded ice flowing off the continent into the oceans, just by being there...." "The grounded ice in the west Antarctic alone could raise sea levels around the world by more than 9 feet...." "things can happen quickly. In 2002, after years of thinning, an Antarctic shelf called Larsen B did collapse in just three weeks. It was the size of Rhode Island."
Many views of Arctic ice are misleading. Warmer temperatures actually increase the snowfall, which makes the sheets appear larger. But the melting occurs from underneath because of warming ocean currents. The ice is no longer anchored to the bedrock in some places.
Big Shelves Of Antarctic Ice Melting Faster Than Scientists Thought
How Much CO2 Can The Oceans Take Up?
Reductions in Oceans' Uptake Capacity Could Speed Up Global Warming
If the permafrost melts in Northern tundra, it will add around 92 gigatons of CO2, more than enough to push us over the tipping point. - Thawing Permafrost: the Arctic's Slow, Giant Carbon Release
Additionally, the warmer Arctic is experiencing blooms of algea, that could accelerate global warming. - Blooming Algae Could Accelerate Arctic Warming
Scientists have considered a 2°C degree increase in global temperature possibly acceptable. A new report says this is madness.
- Time to ‘Do the math’ again: Allowing 2°C global warming is madness
So what we are seeing is the limitations of the environment to deal with additional CO2 emissions, and changes that actually accelerate the release of CO2 and global warming.
The impact on the weather and natural events, such as hurricanes, tornadoes, and storms is proving worse than expected, with California now believed to be in a drought that won't end in the near future and the drought conditions to spread across the US as far as Kansas.
Extreme Heat and Heavy Rain Events Expected to Double
The Western U.S. Could Soon Face the Worst Megadrought in a Millennium
NASA Climate Time Machine - This series of visualizations shows how some of Earth's key climate indicators are changing over time.
This in-depth calculator lets you play around with ways to solve global warming
It may cost us much more in the long run to save the earth. Short-termism and the threat from climate change - McKinsey and Company