Although we typically think of natural disasters as being caused by nature, today we’ll be learning how humans influence both the frequency and intensity of these events.
Humans and Natural Disasters
Floods, hurricanes, droughts, and wildfires can all cause significant damage to humans. Although these events are typically thought of as natural disasters, or a naturally occurring event that causes damage to human life, sometimes they aren’t so natural after all.Since humanity’s beginning, we have been impacting the environment in a costly way. Today, our growing population requires increased agricultural activity, which depends largely on deforestation to create suitable land. Our sprawling cities and consumption of fossil fuels also have a direct impact on the environment.
These activities are also causing changes in global weather patterns, leading to an increase in natural disasters like floods and wildfires. Today, we’re going to look at three problematic human activities and how they increase our risk for natural disasters.
Most people eat some form of animal products throughout the day. Milk, cheese, yogurt, and meat are often a staple in our diets.
Unfortunately, these products are polluting our environment and increasing our risk for natural disasters.Much of the Amazon rainforest is being clear-cut to make way for cattle ranches. The removal of trees during deforestation not only leads to global warming and destroys animal habitats, but it also disrupts the water cycle.
Without trees to absorb rainwater, rainfall easily causes flooding and soil erosion in these areas.In 2004, Hurricane Jeanne heavily damaged Haiti, leading to hundreds of deaths and severe damage to human communities. Scientists have shown that the damage was especially severe due to the massive deforestation in Haiti. Much of its tropical rainforests have been cut down to make way for industry. Without trees to buffer the storm, the death toll of this storm surged.
Surprisingly, deforestation can also lead to severe droughts. Trees are an important part of the water cycle, bringing ground water back into the atmosphere. Less trees means less rainfall, increasing the risk for drought.Another issue with agriculture is crop rotation.
In crop rotation, farmers alternate which crops are grown per season. Different plants need different nutrients from the soil, so rotating crops ensures that no one nutrient becomes completely depleted. So what happens if farmers don’t rotate crops? Nutrients needed for plant growth become scarce in the soil, making it difficult to grow anything. The lack of plants, like deforestation, causes increased risk of flooding, soil erosion, and drought.
Since the Industrial Revolution, air pollution has increased exponentially. One of the biggest problems in the category of air pollution today is global warming.
Put simply, global warming is an increase in the average global temperature of the Earth. Even seemingly small changes, just a few degrees Celsius, can be devastating for our planet. The leading cause of global warming is an increase in greenhouse gases, such as carbon dioxide, methane, and nitrous oxides. These gases enter the atmosphere when we burn fossil fuels, cut down trees, and increase our livestock production as we are currently doing.Global warming has profound effects on our weather patterns in a process known as climate change. As the temperature of our atmosphere increases, glaciers melt and change both ocean temperatures and sea water levels.Our oceans are a large regulator of weather patterns as they play an important role in the water cycle.
Heating and cooling of the oceans influences evaporation, which causes precipitation and sometimes tropical storms. Although still debated, some scientists have correlated increased sea temperatures with the frequency, severity, and destructive power of Atlantic tropical storms. As global warming increases, ocean temperatures rise and storms get worse. In addition, many models show that a continued increase of global warming will lead to more intense storms.Similar to deforestation, global warming not only causes too much precipitation in some areas, but also not enough in others. Since the 1970s, the frequency and severity of droughts has risen, correlating with the increase in global warming.
With changes in weather patterns, dry areas are receiving less rainfall, whereas the intensity of storm rainfall has increased in other areas.Decreased rainfall and drought also cause wildfires, particularly in the dry chaparral of California. In the summer of 2016, California underwent a major drought and subsequently endured intense wildfires that spread for 57 square miles, with more than 37,700 acres burning wildly.
As our human population increases exponentially, our housing needs increase as well. Urbanization is the construction of cities and suburbs in place of natural ecosystems. As with agricultural development, urbanization also causes deforestation and has similar impacts of increased flooding and drought.Another issue with sprawling urbanization is the destruction of floodplains.
Floodplains are areas of land near bodies of water that are prone to flooding. Building in floodplains is risky business due to the obvious risk of flooding. Yet increased demand continues to outweigh the risks for some cities. Unfortunately, building in these areas can have devastating effects for wildlife that call these wet regions home.Puget Sound in Washington State is a popular area to live and work.
An influx in people has caused increased urbanization and building over floodplains. Not only are the humans living there at risk for natural disasters like floods, but it also is damaging to animal life. In Puget Sound, natural Chinook salmon populations have declined tremendously, and the animals that eat the salmon, such as killer whales, have also declined.
Let’s review all that we’ve learned here. Natural disasters are a naturally occurring event that causes damage to human life, but human activity can increase their frequency and intensity.
Deforestation is wiping out trees, causing increased risk for flooding, soil erosion, and drought. Failure to rotate crops, in which farmers alternate which crops are grown per season, also can lead to decreased nutrients in the soil and thus cause a decrease in plant life, which leads to flooding. Global warming, or the rise in the Earth’s temperature, is causing climate change, in which the temperature of our atmosphere increases and glaciers melt, changing both ocean temperatures and sea water levels. This leads to increased risk for hurricanes, floods, droughts, and wildfires, thanks to things like the burning of fossil fuels. Finally, urbanization, or the construction of cities and suburbs in place of nature ecosystems, causes similar effects as deforestation. Urbanization in floodplains can be especially problematic, causing a decline of natural animal populations and an increased risk of flooding for humans.