|Drought, a prolonged period of abnormally low rainfall leading to a shortage of water, is considered the most expensive weather-related disaster in the world, affecting agriculture, ecosystems, and human society / Photo by: CSIRO via Wikimedia Commons|
Hydropower dams are drying up in Zambia and Zimbabwe, which resulted in electricity blackouts that last for more than 18 hours a day. The power crises in these countries, along with South Africa, have exacerbated the economic strain. The gross domestic product in Zimbabwe is projected to shrink this year; Zambia is currently suffering from its slowest expansion in more than two decades, and South Africa is staring down a second recession in as many years.
Aside from the increasing government debts in these countries, a major factor of the worsening power crisis is drought. Drought, a prolonged period of abnormally low rainfall leading to a shortage of water, is considered the most expensive weather-related disaster in the world, affecting agriculture, ecosystems, and human society. For instance, nationwide losses from the US drought of 1988 reached more than $40 billion, which is more than the losses caused by the San Francisco earthquake in 1989, the Mississippi River floods of 1993, and Hurricane Andrew in 1992.
In recent years, reports showed that droughts have been drier and lasted longer compared to other years. In 2012, the central and western US suffered from this period, which resulted in having 81% of the country living in abnormally dry conditions. The drought had caused $30 billion in damages, putting the safety and health of many Americans at risk. Aside from the huge costs, drought can also affect natural resources, wither crops, and threaten endangered species.
The 2017 State of the Climate: Global Drought by Climate.gov, an online source of timely and authoritative scientific data and information about climate, reported that drought can also increase the likelihood of pest infestations, wildfires, and even epidemics. According to the Climate Reality Project, a non-profit organization involved in education and advocacy related to climate change, many regions in the Middle East, Africa, and Asia are suffering from higher air temperatures, drier air, and more severe or frequent droughts.
The Role of Climate Change
While several factors can cause drought, scientists have started to attribute it to climate change. This is because there’s a high potential that increased global temperatures will lead to more precipitation falling, which can cause increased evaporation and transpiration. As a result, the risk of hydrological and agricultural drought rises. Warmer temperatures also increase evaporation in plant soils, reducing rainfall even more and affecting plant life.
However, it took quite some time before scientists finally linked drought with climate change. In 2013, the fifth assessment report of the Intergovernmental Panel on Climate Change (IPCC) concluded that there was low confidence that any significant trends in drought could be detected or attributed to climate change. But with the emergence of state-of-the-art models and techniques, the researchers’ understanding of drought and climate change has improved.
For instance, the Mediterranean suffered an increased drought due to climate change. Also, warmer temperatures have prompted snow and soil moisture to record-breaking deficits along the Pacific coast of the US. In the Upper Colorado river basin, warmer temperatures have even caused significant river flow deficits despite near-normal levels of precipitation.
|While several factors can cause drought, scientists have started to attribute it to climate change. This is because there’s a high potential that increased global temperatures will lead to more precipitation falling, which can cause increased evaporation and transpiration / Photo by: Muhammad Ali Bilal via Wikimedia Commons|
According to Carbon Brief, a UK-based website designed to improve the understanding of climate change both in terms of the science and the policy response, droughts can increase evaporative losses from the surface, which shifts precipitation from snow to rain and causes earlier snowmelt. A recent study conducted by scientists from Columbia University’s Earth Institute confirmed what most experts fear: that the rise of human-generated greenhouse gases was affecting global drought conditions.
The researchers used studies of tree rings that not only forecast future scenarios on our planet but also shed light on historical trends. “These tree-ring reconstructions let us go back in time and get a picture of global drought conditions for hundreds of years before the Industrial Revolution,” said Kate Marvel, an associate research scientist at the Earth Institute and NASA's Goddard Institute for Space Studies and the lead author of the study.
Gregory R. Quetin, a postdoctoral researcher at Stanford's Department of Earth System Sciences, who was not involved in the study, described the research as “powerful” because of how tree rings alone showed the climate record. “The trees are responding to temperature and the presence of, or lack of, rainfall so they give you these observations—and another path of evidence that this is occurring,” Quetin said.
Major Impacts of Droughts
According to The Conversation, a network of not-for-profit media outlets that publish news stories written by academics and researchers, droughts are multidimensional. For instance, a seasonal-scale drought that reduces soil moisture on a farm as well as a decade-long drought that decreases reservoirs and groundwater supplies can each be devastating but in different ways.
Nonetheless, droughts can have serious consequences on people’s livelihoods. It can affect water supply, people’s health, transportation, and agriculture. Reports showed that 1.3 billion people or 40% of the world population relies on agriculture as its main source of income. Thus, severe droughts can risk not crops but also the lives of people and animals in a certain region affected by it. Also, this has fueled damaging and sometimes deadly wildfires in many countries across the world. For the past decade, millions of forested acres and thousands of homes have been lost due to fires thriving in dry, stressed forests.
While droughts can be difficult to solve, especially in the current status of our planet, people can help not worsen it any further by monitoring and measuring supply and uses, reducing indoor water use, increasing recycling and reuse of water, and other ways.
|Nonetheless, droughts can have serious consequences on people’s livelihoods. It can affect water supply, people’s health, transportation, and agriculture / Photo by: USAID Africa Bureau via Wikimedia Commons|