Tuesday 28 November 2017

Loss of biodiversity - the scope of the problem

This post is a part of the Manitou Initiative series of articles.

A very quick version of the problem of biodiversity loss:
  • The earth's ecosystems consist of the interconnected webs of species (plants, animals, fungi, micro-organisms) living together in different locations around the world.
  • Humanity relies on these ecosystems for our very survival - they produce the fresh water, clean air, food, wood and other natural products that are indispensable to our lives.
  • The earth's ecosystems are currently being vastly disrupted by human activity causing species to go extinct, and the health of ecosystems to diminish
  • We need to change how humanity acts in the world so that we can preserve and repair ecosystems and stop extinctions, if not for the sake of other forms of life, then for ourselves. 
And for a little bit longer version...
There are millions of species on the earth. The exact number is not known, but best estimates are that there are as many as ten million, with over one million having been identified by scientists. Ten million is a huge number, but a finite one. It has taken billions of years to produce these species, all of the animals, plants, fungi, and micro-organisms on the planet. Though there are many species, each is unique, and if they go extinct, they are gone forever.

Ecosystems are groups of species that all live together in a certain area. There can be many thousands of species, and they constantly interact and rely on each other to maintain the integrity of the whole. Plants form the basis of the food chain, taking energy from the sun and turning it into living tissue. Different plants fill different niches, some as tall trees, as grass, as climbing vines, some dropping their leaves for the winter and others keeping them all year. There are animals eating plants, other animals eating those animals, fungi decomposing everything that dies to recycle nutrients and begin the growth anew. Micro-organisms are found by the trillions in every nook and cranny.

While some (myself included) could wax poetic about the grandeur of wild spaces, of the beauty of old growth forests, or the thought of herds of bison roaming the prairies, providing beauty is far from the only thing that ecosystems do for us. Critical to the very survival of humanity are all of the things that ecosystems do for us, often called ecosystem services. Intact ecosystems provide us with soil, food, water, medicine, wood and other plant fiber, they maintain climate and rainfall patterns, and more. To provide all of these functions that we hold so dear, ecosystems need to be maintained in a healthy state. There are innumerable instances where people's damaging of lands and waters led directly to massive problems in human society. Floods, soil erosion, desertification, wildfires, polluted water, can all be caused by poor management practices, and can threaten the very foundations of societies. In today's world, climate change is linked tightly with ecosystem damage, as poor forest management and poor agricultural practices are some of the main drivers of a warming planet. In terms of species extinction, it is estimated that current human practices are causing the rate of species extinction to be a thousand times higher than what it was before the modern age, and we are currently be losing thousands of species every single year.

People need to act now to preserve ecosystems and species. We know that ecosystems are resilient, but it is unclear how much abuse they can take before problems may spiral out of control. There is something called the precautionary principle that tells us that we shouldn't take dangerous actions when we are unsure of how risky they are. The cost of doing nothing could be absolutely immense, whereas if we act now to change 'business as usual', we know that this is likely to lead to great outcomes for both people and the planet. There will be some costs associated with making these changes, but the long-term benefits to saving ecosystems and species far outweigh the short-term benefits of massive scale clear-cut logging or agricultural practices that destroy the fertility of the soil.



Sunday 19 November 2017

Global climate change - the scope of the problem

This post is a part of the Manitou Initiative series of articles.

The super short version of the problem of global climate change is as follows:
  • Carbon dioxide and other greenhouse gases in the atmosphere trap heat from the sun
  • People are vastly increasing the amount of greenhouse gases in the atmosphere, which means we trap more heat, which means the temperature of the planet is rising
  • A fast rising temperature causes massive problems for humanity and all other life on earth
  • We need to stop putting extra greenhouse gases into the atmosphere if we want a livable and sustainable world
I'll unpack it a bit further in the following paragraphs, but will keep it to a few paragraphs as there are a great many resources that outline the ins and outs of climate change.

First, there is a natural carbon cycle on the planet. Carbon is a basic physical element, found in great quantities both on the surface and in the center of the earth, though it makes up only a small proportion of all of the matter of the earth. Most of this carbon is under the surface, bound up in rocks, in the earth's core, or in fossilized plants that have been buried by the action of water, wind, and time. Then there is the carbon found on or near the surface that cycles back and forth between the air, the water, the rocks and soil, and living things. All life that we know is built out of carbon molecules, and all living things spend much of their time and energy bringing carbon into their bodies. Plants draw it from the air while animals eat other living things made out of carbon. The earth's cycle of carbon is always in flux, plants are growing and dying, animal populations rise and fall, rocks and water absorb and release it. The main point to make about the cycle is that the amount of carbon actively moving around the surface, the waters, and the atmosphere, has stayed in equilibrium for millions of years. The equilibrium amount of carbon in the atmosphere, mostly as carbon dioxide, has stayed about 300 parts per million (a quite small proportion of the air) for at least hundreds of thousands of years up until about one hundred years ago.

The problem that we face today is that people have thrown off this balance, as human activities have drastically increased the amount of carbon going into the atmosphere, much more than the natural systems and cycles can absorb. The most notorious source has been the fossil fuels of coal, oil, and natural gas. These substances once were living organisms, and were trapped underground and transformed into concentrated carbon based energy. When we burn them, we release carbon back into the atmosphere that has been out of circulation for millions of years. Another huge contributor to carbon in the atmosphere is poor land use. For example, forests are cut down, poor agricultural practices destroy soil, cows produce lots of methane (another carbon based greenhouse gas), all of which lead to the carbon stored in these places being released to the atmosphere. Industrial processes can also add carbon to the atmosphere. One such process is the production of cement. Cement is made by heating rock (limestone) that is high in carbon, leading both to a useful product as well putting more carbon dioxide into the atmosphere. The sum of these activities cause the amount of carbon in the atmosphere to rise. Today in the fall of 2017, the amount of carbon dioxide in the atmosphere has risen by a third, to 405 ppm. Current human activities are causing a continued 1 ppm increase each and every year.

Now, the biggest reason that all of this extra carbon in the atmosphere is a problem is due to the greenhouse effect. The basic analogy of the greenhouse effect is that the glass walls of a greenhouse trap some of the energy from the sun, allowing the inside of a greenhouse to be warmer than the air outside. It turns out that the earth's atmosphere does the same thing. An enormous amount of energy from the sun hits the earth, with some staying and some bouncing back into space. Carbon dioxide and other greenhouse gases in the atmosphere do the same thing as the glass in the greenhouse walls, they trap heat inside. The more greenhouse gases in the atmosphere, the warmer the earth stays. This has mostly been a great thing for life on earth, as the greenhouse effect is the reason that we have such moderate temperatures today that life on earth is so well adapted to. As mentioned in the last paragraph, carbon dioxide in the atmosphere has risen by a third, and this has trapped more heat through the greenhouse effect. So far, this rise in atmospheric carbon has increased the earth's temperature by nearly one degree Celsius. If current trends of humanity's resource and land use continue, this could reach 5 or 6 degrees Celsius (10 degrees Fahrenheit) by the year 2100. Humanity now stands at a point where we are cooking ourselves out of house and home. It is impossible to predict all the effects of this warming, but we do know that it would be catastrophic. Sea levels would rise, weather extremes of flood, drought and wildfire would increase, some ecosystems would collapse and many species would go extinct, and there would be millions of climate refugees fleeing these effects.

Put all together this makes for a very simple goal in fighting climate change, though it will be difficult and complex to achieve: humanity needs to stop putting excess greenhouse gases into the atmosphere if we want to save ourselves and our planet.