I read geography at university and so, including at 'A' level, I studied that subject (in between playing cricket and rugby) for 5 years. Geography is a study of the relationships between people and their environments across space and time.
I always found geomorphology, the study of landforms and the processes that create them, much more interesting than human geography which is the way people react to and live within those environments.
Like everyone else, I have experienced some of the natural processes such as wind, rain and temperature extremes that shape the earth. I have seen glaciers but have never walked near or examined one - a study of a glacier is impossible when sitting in an aircraft flying 20,000 feet above the Alps. There are many natural phenomena that I have never seen, felt or heard.
But, I have experienced two earthquakes.
My first earthquake was on July 26th, 1963. I was 16 years old and on a camping holiday with my parents and Peter, my younger brother. The earthquake was sizeable, measuring 6.1 on the Richter scale. More than 1,000 people died; 4,000 people were injured and 200,000 were left homeless. The quake happened at 5:20 a.m. when most people were still in bed.
We were camped on a hill about a mile from the centre of Skopje which is a city in North Macedonia or Yugoslavia as it was then. Amazing as it seems, we all slept through it. I wish I knew the manufacturer of the camp beds we were on. Think of the advertising possibilities:
“THE BEDROOM COLLAPSED BUT I SLEPT THROUGH”
We only became aware of what had happened when, after breakfast, we drove towards the city centre and found that all the roads were closed.
The second one was on January 19th, 2010, at 9:23 a.m. As usual at that time of the day, I was sitting in my recliner in the living room of our cottage in Prospect, Grand Cayman reading the online Times newspaper.
The chair suddenly began to shudder and a framed photograph fell from the wall shattering the glass on the tiled floor. There was no sound and the shaking lasted for about 15 seconds. Instead of the sea being flat calm, it looked choppy as though a steady breeze were blowing across it.
It ended as suddenly as it had begun and within a minute of the cessation of the agitation, the sea was flat once more. It was a 5.8 magnitude earthquake and its epicentre had been 40 miles away and at a depth of 6.2 miles. There were no accounts of injuries on any of the three Cayman Islands and no structural damage was reported.
Experience of the tremor was very localised. At the primary school where I helped out two days a week, I was told that one block of four classrooms felt nothing, whereas in the rest of the school, the children and their teachers followed the emergency procedure and sought refuge under the tables. People who were driving on the island, felt nothing.
Exactly a week earlier Haiti, which is only 590 miles from Grand Cayman, had experienced a 7.0 magnitude earthquake. Almost 300,000 people were killed. When Cayman’s earthquake happened, many Caymanians panicked and there were reports of parents barging into schools and taking their children home.
The Richter scale is logarithmic and so the magnitude 6.1 earthquake at Skopje - that I didn’t notice - was twice as powerful as the 5.8 Cayman earthquake that shook me in my chair. A difference of 0.3 on the scale is much bigger than it seems, as a magnitude 6 earthquake releases approximately 32 times more energy than a magnitude 5 earthquake.
Volcanos and earthquakes are found together at the margins of continental plates. I have never seen an active volcano but in 2011, Caroline and I went to Dominica, which has 9 volcanos that are classified as active but a volcano doesn’t have to be erupting now to be classed as active. Any activity that has occurred in the current epoch, which began around 12,000 years ago, makes it technically active.
The last volcanic activity in Dominica was in 1997 although that was more of a fart than a full on evacuation of lava. No lava was emitted and only a relatively small area was covered in ash. Needless to say, while we were there, we saw no activity.
As I’ve written before, (Click Here), we did witness a total solar eclipse in 1999 and the vivid beauty of it remains imprinted in my memory.
While sitting in a restaurant on the bank of the Gironde estuary in August this year, I saw a tidal bore and managed to film it.
To see it better, go to full screen.
Bores happen when an incoming tide is forced up a funnel‑shaped, shallow estuary. That water piles up so that the incoming tide is strong enough to produce a travelling wave that moves upstream against the river’s flow.
The height of that Gironde bore appeared to be less than a metre, whereas in the UK, the River Severn’s bore travels for several miles and so creates an upstream wave which is typically around 2 - 2.5 metres above the river level. People surf it. The Gironde has less of a rate of narrowing and so the bore is weaker.
I think I have seen a drumlin which is an oval hill. Drumlins are formed when ice passes over unconsolidated glacial till, the unsorted sediment that forms a ground moraine. I was being interviewed by Professor Fisher, the head of the geography department at Durham University.
After about five minutes, he pointed out of his office window and asked, “What’s that?” All I saw was a rounded hill. “A drumlin?” I suggested.
He said nothing but asked me something about landforms in a hot desert. I assume that I was right but he never told me or mentioned it again.
Living on Grand Cayman for five years made me realise that some of the “facts” that I had been taught in ‘A’ level geography and that I had taught students for 30 years were just wrong.
There certainly are seasons in the tropics. The Poinciana tree blooms in the beginning of June and stays in flower until late July and that is also the period when Mangoes ripen.
Royal Poincina tree
It does not rain in mid-afternoon on most days in the tropics as I had thought. There are wet and dry seasons. The rainy season is from May until November when there is an average of around 180mm of rain a month. The dry season has around 40mm of rain a month.
I had learnt about buttress roots and they are more spectacular than I imagined. Some trees in the tropics are shallowly rooted but those roots are large and wide roots . They help to prevent the tree from falling over during a hurricane, hence the name buttress.
It would take a very powerful hurricane to blow that thing over and as you can see from its buttress roots, the tree is pretty secure too.
Carolina and I joined the Cayman Astronomical Society. Cayman has virtually no light pollution and we once spent a wonderful evening glued to a powerful Celestron telescope looking at Saturn with its rings clearly visible in fine detail.
The last thing I saw in Cayman that I had learnt about but never seen was a mangrove swamp and much of Grand Cayman’s undeveloped coastline is covered with them.
Features that I would like to see and could with some planning and luck are the northern lights, a tornado and an erupting volcano.
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