Building the greenhouse: are we paving the way to climate change?

Even if we somehow magically minimised to zero our carbon emissions from industry, transport and domestic sources, the excess of carbon dioxide in the atmosphere may not be reduced a great deal, and may even continue to increase. Why? Because we are making too many shadows.

Every built structure, be it a road, a house, or even a wooden fence, interacts with incoming solar energy, which arrives mostly as light. In the natural world, light falls on natural surfaces: rocks, water, sand, but most importantly, vegetation. More specifically, the leaves of plants.

Photosynthesis is the most efficient mechanism for absorbing light energy, and converting it to chemical potential energy, that we are aware of. While photovoltaic cells may be capable of utilising more of the visible light spectrum, (plants only use the red and blue wavelengths), and may actually be more efficient at absorbing the light and converting it to a storable form, (electricity), plants still have an advantage: They remove carbon dioxide from the air as they function.

The chemical result of photosynthesis are sugars, an important component of which is carbon. Plants take carbon from the atmosphere, and combine it with hydrogen from water, releasing oxygen in the process. The efficiency of this reaction is, assuming adequate water supplies are available, limited mainly by how much light energy is available. The more light, the higher the rate of photosynthesis, and consequently, the higher the rate at which carbon may be drawn from the air.

Shade from buildings, fences and other human structures prevents light from landing on the photosynthetic surface of plants. Further, paved areas, such as roads and pathways, reduce the available area for plant growth which clearly reduces potential carbon absorption. The other effect they have is to absorb and reflect energy form the sun. Absorbed energy is converted into low level heat, which on a local scale can affaect weather patterns, and change climatic conditions. On a larger scale, the effect is probably less obvious, but reflected energy is trapped by the natural (and enhanced) greenhouse effect, contributing to climate change.

More awareness of these issues in the design and construction of human shelter, communication and transportation necessities is required if a serious and lasting solution to climate change is to be achieved.

Drawing on his inner vision

The other day I happened by the library where I work, and stumbled upon a huge pile of old New Scientist magazines they were discarding. So, naturally, I picked up the stack and put them in my office, and have been progressively, if randomly, getting through them as I journey to and from the campus each day. Okay, they are a little out of date, but there's always something in every issue to hold my attention, and as most articles are short, it's perfect for the stop/start of public transport.

One story, from January 2005, caught my eye, and my imagination, as the very topic itself had come up in a lively informal discussion of philosophy only recently (at the pub). We were wondering if someone who was born blind could have any concept of colour, space, perspective, and pretty much all the things we sighted people take for granted. It turns out that, yes, they can.

Esref Armagan is an artist, whose paintings show an understanding of colour, perspective, light and shadow that belie the fact he is clinically blind, and his brain receives absolutely no information from his eyes about the lit world around him. Scientists scanning his brain revealed that even though his eyes have literally no function (he was effectively born blind) his visual cortex is active when he draws. This is similar to the activity of a braille readers visual cortex when they feel a page of text.

Some researchers feel this shows our understanding of what sight, and indeed all our senses, actually are needs some revision. A lot of revision. It is certainly clear that our "basic" senses are not the only source of understanding of the world around us, which seems to be more to do with how our brains process information than the form in which it is delivered to them. Below is a video, showing Aramagan composing a new drawing.