Notes on “Dr. Art’s guide to planet Earth”
So you sometimes get amazed by the beauty and perfection of our home the planet Earth. There are green trees, beautiful rivers, meadows, useful animals, crops, mountains and above all life on our planet.
Usually we take all these things for granted and try very little or nothing at all to know what is going on “behind the scenes” that makes up and keeps running such an environment where life can grow and sustain.
“Dr. Art’s guide to planet Earth” is that interesting read, which can guide you to the planet earth in a unique, gentle and layman way and does not let the interest drawn away at any point by darn scientific facts and terms.
Earth as a System
The book starts off by introducing the System Thinking. We all know that a system is a combination of different parts which work as a whole. We learn to see planet earth from a system perspective and come to know that the earth system can be described as consisting of three main parts: Matter, Life and Energy
Look around you, you will find out matter everywhere. Earth system mostly consists of matter, which exists in solid, liquid and gas forms. But where did all this matter come from? Earth parted from the sun some four billion years ago and since then, has been circling around it. All the matter on Earth is the same since then. The big idea is; Earth is a closed system with respect to matter. That is; no new matter is produced on earth now and no matter leaves it. Woo!
But that does not mean matter stays at the same place, it cycles. Earth is a recycling system; the same matter gets used over and over again. We all are very familiar with the water cycle — water evaporating from earth surface, forming clouds and then coming back in the form of rain. But amazing thing is even solid and gas stuff cycles. Rock on earth surface are continually broken down by forces of flowing water and chemical reactions but a parallel process of new crust building keeps taking place from lava and earth plates movement.
Energy is what needed to carry on processes on earth. With respect to energy earth is an open system; it relies on a constant inflow of energy from sun that is used in virtually all the processes that keeps earth system going. Earth also radiates energy back outside to keep balance of temperature; otherwise it would become too hot and boil away.
A large amount of solar energy is absorbed by solid materials and water and converted to heat. That heat evaporates the water and power the water cycle. Some part of that energy is absorbed by Plants and converted to chemical energy which is used in photosynthesis for making food for us. Our bodies also absorb solar energy to keep warm. So the take away is Energy flows and changes forms.
Although in terms of biomass life is only 1 percent of the earth’s total mass but it is immensely diverse, the estimation of different species is 5 to 30 million and more. Life on earth is interconnected where every organism depends and significantly affects other.
A significant example; the plants are earth’s producers. Plants capture energy from sun, take water and carbon dioxide from the environment and through photosynthesis create sugars and release oxygen. The rest of organisms are consumers either eating plants or other animals. The plants rely on animals for pollination and on decomposers for creating rich soil from dead waste.
The animals also internally burn the sugars from plants and release carbon dioxide into the environment which the plants inhale. So at each moment life is depending on each other.
The book also discusses the environment issues and use system thinking to analyse how a change in environment can affect the involved earth system. The last chapter deals with how we can act locally to less affect the earth’s system.