Explaining climate change
Aggressive agriculture without thoughtful planning has changed quite a bit of the Earth’s surface — irreversibly. About 40 percent of our planet’s land area is agricultural. And most of that is not done sustainably, with any eye toward preserving soil or natural conditions.
We first got an inkling of how important this was almost a hundred years ago during the Dust Bowl. For three decades before WWII, millions of acres of thriving native grassland in the southern Plains were turned into wheat fields. But the one-two punch of the Great Depression and the Great Drought, caused dust storms to move tons of dry soil that had previously been kept in place by the native grasses.
These grasslands, which had evolved over the thousands of years since the last Glaciation, had created a delicate equilibrium with the climate extremes of the Plains, keeping the fertile soil in place. Now they were gone.
From North Dakota to Texas, much of the Great Plains became a desert.
Just 5,500 years ago, giraffes, hippos, lions, and antelopes roamed lands lush in vegetation and vast wetlands in what is now the Sahara Desert. Climate change and overgrazing changed it within only a few decades.
The same happens with forests.
There are three major types of forests, classified according to increasing latitude: Tropical, Temperate and Boreal. More than half of tropical forests have already been destroyed. Only scattered remnants of original temperate forests remain, many of them in Washington State. Ongoing extensive logging in boreal forests will soon cause their complete disappearance.
Sometimes we plant trees on the logged areas, but at best it becomes a mono-culture crop, not a forest. The forest microclimate, soil and animals are all gone.
This is what happened in the Moors of England. They were once covered by dense forests with thick soils, but Iron Age humans clear-cut these forests to smelt iron. They never grew back.
There can be no regrowth of most clear-cut boreal or temperate forests since the post-glacial environment that formed them is gone. They can maintain their own microclimate that allows them to continue, but once that’s destroyed by clear-cutting, that’s it.
Besides the lost forests, their microclimates and indigenous species, a huge amount of soil is lost with clear-cutting, particularly the nutrient-rich top soil. These ecosystems normally hold the soil from eroding. This soil has almost as much carbon in it as the forests, further contributing to global warming.
But forest fires provide the most dire change to global ecosystems. Forests provide more than just economic and recreational services. They contribute to climatic and hydrologic regulation of their landscape. Fires are a natural phenomenon from which most forests normally recover. But climate change and human activities exacerbate the effects of wildfires and causes rapid permanent ecosystem destruction.
A 2016 study reported that the burnt area in the northwestern United States expanded by almost 5,000 percent since 2000.
The fire seasons around the world are expanding, starting months earlier in the spring and going months later into the fall, caused by once-rare droughts. In a vicious cycle, deforestation leads to an increase in fire frequency, which in turn inhibits the regrowth of forest vegetation.
The Washington State Department of Natural Resources (DNR) is worried about this summer’s fire dangers in eastern Washington. We’re already hotter than usual. “This is becoming the norm,” explained DNR spokesperson Janet Pearce. “Last year our fire season started a little earlier and this year on the west side we had about 50 fires in March and that’s not typical. On the east side, we’re very concerned because it’s almost all in drought-like conditions and that could make for a challenging fire year.”
But another phenomenon is also occurring — the public might be getting Catastrophe Fatigue with all the Doom and Gloom coming from the scientific community. But while we’re telling the public what’s going on, and many are finally listening, nothing is really happening to change things.
Most of the conditions under which the global ecosystems evolved are no longer here for them to recover. We won’t get them back. But we should preserve what is left.