Defined as a period of below-average precipitation sometimes coupled with increased temperatures, drought is an issues that has arisen for a multitude of reason throughout the years. Known to last several years – the longest recorded one lasted over 400 – droughts can have a dramatic effect on agricultural, the environment and local socio-economics. From the seasonal droughts that befall those in the dry tropics, to more rare large scale events in various areas around the world, droughts are a serious issue that doesn’t often get much attention.
Apart from the obvious problem caused by a drought: land degradation, reduction of available water resources, potential for crop failures and livestock death as well as negative effects on our own wellbeing, there are also many other dangerous side-effects. Increases in temperatures and arid climates make for great wildfire conditions, you need look no further to this year’s droughts in areas like California, Portugal or Australia as precursors to the fires experienced in those countries.
Whilst some are a seasonal by-product of natural El Nino-Southern Oscillation (ENSO) or other local meteorological factors, climate change has exacerbated many environments and pushed local ecology to its limits with unusual droughts. Areas in Papua New Guinea, Africa, South America and even the United States have already suffered from these droughts, which have led to crop failure, extreme temperatures and deaths.
There are three main drought classifications, all with different causes and effects. Meteorological droughts are the first stage of droughts, and are brought about when there is a prolonged time with less than average precipitation. Following the conditions of meteorological droughts are more important agricultural droughts, which affect crop production and local ecology – everything from your household pet to us, as well as all local wildlife. These droughts can also be caused by poor soil conditions, land degradation or a lack of normally available water.
This brings us to the final, much more severe type of drought which scientists believe will become more common in the future: hydrological droughts. These droughts, which have already happened in several countries after years of climate change induced alterations to local climate – to name a few: Syria, Papua New Guinea, Venezuela and Australia. Hydrological droughts are caused by a lack of total available water, when lakes, aquifers, reservoirs and dams all fall below acceptable thresholds and cause widespread water shortages. Whilst these can also be caused by physical activity such as large scale agricultural ventures essentially draining the Dead Sea, it is expected that increased temperatures as a result of climate change will only aggravate drought conditions in a range of countries, potentially destabilizing political and socio-economic factors to the same extent as what has been seen in Syria.