Rain is a gift. It washes the land of dust and grime and it permeates the soil to feed the plants that feed us: well, most of the time it is.
The small city on the east coast of Taiwan where I live has just had 900mm of rain in three days, after one of the longest dry spells in history and after the longest prolonged period with temperatures in excess of 34 degrees since records began. You might think that rain after such a long drought would be welcome. You’d be wrong.
The average annual rainfall for the city, which is approximately 60km north of the Tropic of Cancer, is 2000mm. We had almost half our annual rainfall in three days. When rain falls as it did over the past weekend, it does much more harm than good. Many people have never experienced tropical rainstorms so if you need a reference, think about walking through a waterfall and you’ll have a rough idea. To give you an idea of the amount of rainfall that we had, the average annual UK rainfall is about 800mm and the wettest cities in North America get an annual rainfall of about 1100mm, so in three days we had the amount of rain that most of you see in a year.
You might think that the farmers would love it. You’d be wrong. Rain that is this heavy destroys crops and washes millions of tonnes of soil into the rivers and off to the sea. That is soil that cannot be used to grow crops in the future. The most vital farming real estate literally floats away. It also rushes straight to the rivers and down to the sea. Unlike rain that falls in more manageable amounts and which is stopped before it reaches a river or the sea and sinks to replenish the water table, the rain that we have just experienced creates rapid torrents that rush straight off the top of the land and leave the water table unaffected. The water table, which is falling annually, is not replenished, so next year’s crops will have less water than this year’s.
If the farmers don’t love it then surely the authorities must be glad that the reservoirs are full again. I’m afraid not. The water that fills the reservoirs is full of debris because of the destructive power of such a large body of water moving at high speed across the surface of the land brings dirt that clogs filters and larger pieces of agricultural detritus that smash them, so the repair bill is astronomical. The only solution is to remove the filters for a while and allow the filthy water to flow into the water supply.
Ten years ago, when I first came to Taiwan, there were one or two big storms a year and a rainy season, during which the water table was maintained at a fairly constant level. Most of the rain fell outside the times of storm and although the showers were extremely heavy, rain fell in manageably small amounts and a high percentage of the groundwater was retained by the land. In the recent past, more of the rainfall has occurred in short bursts that destroy more than they feed, so it is wasted rain. The steady supplies of rain that feed the land have not been seen for many years.
Water is not always the gift that it seems. Vietnam, Laos and southern China are experiencing similar problems with rain that is useless, so the price of vegetables is rising. Instead of a steady supply of rain in the early summer and fairly regular downpours throughout the hot months, when the crops need it, the typhoons are coming later because the seas are hotter and the rain falls at a time when many of the fields are fallow.
There are still sceptics who do not believe in global warming. One of them is the president of the United States. A factor that most of these sceptics share is that they live at latitudes that are far from the Equator. The greatest effects of heating are naturally first felt in the areas of the earth that are hottest. The more extreme effects of climate change are now being regularly felt in Northern California and Portugal, which are at latitudes of about 38°N. By my calculations, the most extreme effects of climate change in the Northern Hemisphere are moving northward at about a degree of latitude per year, so northern Europe has about another 12 years of grace.
Many people tell me that we are mad to think about returning to Ireland, which is at 54°N, and has weather that still produces natives who have a strangely pale blue complexion. We are not mad. We are just doing what most humans do naturally in that we are gravitating towards heat. One subtle difference in our strategy is that while we still can, we are moving a full thirty degrees of latitude northward to swap searing heat that creates chaos that is beyond any human control for heat that is still manageable and a climate that is still bearable, although imperfect in other respects. I have come to the conclusion that the reason why the sceptics so obstinately refuse to believe what is right before their eyes is that it is not before their eyes: It is all happening ten to thirty degrees south of them.
Go north young man.