Derek – Friday 28th August 2020
Two weeks ago we had four consecutive days with temperatures over 30ºC. Now the temperature is below 20°. Summer is past; autumn has rushed in with two storms from across the Irish Sea, Ellen and Francis.
If you’d just beamed yourself in somehow through a wormhole, a walk round our garden would tell you the time of year. There are few flowers. A few persistent California poppies, the odd rose, and Michaelmas daisies which are in season anyway, but hollyhocks and globe thistles are gone. A few buddleia flowers hang on, but not much longer as we are cutting the jungle back, as we do this time of year. We have stripped the wildflower bed. Enough seed has fallen to keep it going next year.
It’s spider time, the webs come with autumn. The arachnids have matured over spring and summer and now must mate before they are killed by frost. Their legacy is the egg sacs which will hatch in the spring to continue the cycle.
The annuals are done, flowered, gone to seed, dead or dying. Typical are the teasels; the stiff brushlike heads are atop dead foliage and stalks. Bristly ox tongue, so handsome in late spring with its pimply leaves and dandelion-like flowers, becomes ragged and languid over the summer. I look online to see if it is an annual, but several sites say it is an annual or biennial. So take your choice. The biennials, presumably, being young plants emerging in the autumn which will mature next spring.
The cereals have taken a pasting in the high winds and rain. Wheat, barley, rye and oats are smashed. This is the weather that farmers dread at harvest time. Whole crop can be ruined. The dwarf maize’s multi-coloured cobs are ripe, perhaps over ripe. I cut them off, and pull back their outer leafy layer, woodlice and earwigs crawl out. I photograph the small cobs. I look at the sweetcorn cobs. They’re not ready, and with this cold wet weather will they ever be?
The Gateway site next door rises floor by floor. There will be 114 flats when completed. Architecturally, it is uninspiring. The site is cramped and the individual blocks are box-like. There is no resident parking, which is positive in terms of future carbon footprint. But all the concrete in the floors, walls, stairs, and pavements gives the building a huge carbon footprint from this component.
When we think of the contributors to climate change, we tend to think of fossil fuels. Frequently overlooked is cement, a major constituent of concrete. Cement accounts for 8% of global carbon dioxide emissions. Think of all those multi-storey buildings, motorways, pavements, and sites like that next door, and consider how ubiquitous that grey stone is. It’s tough, it weathers well, and it is cheap.
Over its manufacture, a tonne of cement equates to roughly a ton of carbon dioxide. Cement is made from limestone, which is a form of calcium carbonate. The limestone is heated in kilns at 1400ºC, to form quicklime, giving off copious CO2 as the carbonate breaks down. Added to this direct carbon dioxide is that from the fuel firing the kilns, the fuel for quarrying and for transportation.
There are greener cements where some of the cement is replaced by various materials such as slag from steel works, clay, or by magnesium oxychloride. Much research is going on to produce totally green replacements, but the construction industry is conservative and only government directives can bring about large scale use of green cements. Which brings it back to me and you. Governments only act on climate change when people make a fuss.
Share your thoughts