The landslides in the area are not natural as if humans didn’t build on the land and if they didn’t clear away the forest, the forests would still be able to absorb some of the rainwater and wouldn’t loosen the underlying soil causing it to slip. However if there was no rain then there would be no problems but as this isn’t true the main reason why the landslides and deaths may occur is due to people not abiding by the law and living and building unsuitable houses in unsuitable areas.
People are increasingly living in areas where hazards can occur. Currently, 500 million people live on or near volcanoes. They live in these areas as the volcanic ash makes very fertile soil, which is good for growing crops which in turn brings in an income which supports their livelihood. Volcanoes are also very beautiful places and people enjoy living in view of them and they erupt pretty infrequently so feel there the benefits are greater than the risks. Some people are however are driven nearer to volcanoes as land is more sparse. In Mexico City, millions live in the shadow of the massive volcano Popocatepetl. The world’s best coffee is grown on volcanic soil. The region around Naples, Italy, one of the richest farming areas in the world, is built in part on volcanic ash from nearby Vesuvius. The lower slopes of Mayon are covered with rice fields and coconut plantations; tomatoes and other vegetables grow further uphill. Farming the soil of an active volcano is inherently risky. for poorer residents, however, it is often the only livelihood available. Mayon’s eruption in 1993 killed 75 people – all of them tomato farmers in the Bonga Valley, one of the ravines declared off-limits by the government. Today nearly 20,000 locals live and farm within Mayon’s Permanent Danger Zone. Half of these farmers refused to evacuate during the most recent eruption. Others returned surreptiously to lend their fields and animals: without their crops, they risked starvation.
Humans don’t cause the volcano to occur but they do put themselves at risk by living to close to it. If no civilisation was present near them, so when they do erupt nothing was damaged or hurt it couldn’t really be classed as a hazard but as an event. Only the presence of people living there and getting injured and loosing their houses and crops etc make it the hazard so therefore the volcano itself is natural but it being a hazard could have been avoided.
The mountains can be places to visit, many people like to ski, others like to climb while others like just to visit to admire and take photos of its beauty. Humans cause 90 % of all avalanches. When skiers go off piste to ski in the fresh newly dropped unskiied snow they ski over snow which is weak and unstable as it has not been compressed yet and the snow cover cannot support the that new layer so it breaks off in a slab and starts flowing down hill moving up to 125mph. All across the world every year people are killed by avalanches on average over 200 people die, it is estimated that 1 million avalanches occur every year worldwide. In February 1999 an avalanche occurred in Chamonix, France, 10 people were killed, 11 rescued unhurt, five with minor injuries, one seriously injured, two believed to be missing. Not only did this avalanche effect people in Chamonix but also affected surrounding ski resorts, destroying chalets and buildings. Avalanches would not occur if skiers were not on the slopes triggering them off in the first place this is why I feel avalanches are not natural, yes they would occur if no humans were present but their likelihood is much greater with the influence of humans.
People do have to live somewhere and most people have little choice about where they live. Over the last 10 years more than 2 million new properties have been built, urbanising a massive area of land, and has resulted in water running off into rivers at a much faster rate, causing higher flood peaks and greater risk. This is made worse where developments have taken place on floodplains. Agricultural intensification has also improved drainage, accentuated by over-grazing and soil compaction which reduces the ability of land to soak up water. In the last 25 years we,ve also drained and filled in 60% of our floodplain water meadows which once acted as a natural safety valve, holding back floodwaters and reducing flooding risk downstream. Floodplains are prime sites for human beings in all areas of the world. They are fertile for agriculture, often sheltered, flat for building and near a fresh water supply. As a result many UK cities, towns and villages are built on river floodplains. This stops the floodplain being able to absorb excess river water and so it has to go somewhere. The stone and concrete people build settlements with is non-absorbent and water flows over it very quickly. We also collect huge amounts surface run-off water in our drains. Instead of allowing a floodplain to absorb excess water, we channel a lot of it very quickly away from our settlements, inundating river channels and areas downstream with potential floodwater. Similarly, we have built flood defences in many of our riverside settlements to protect them from river flooding. When trying to put solutions in to help prevent flooding you just push the problem further downstream and onto someone else, never really solving the problem. The drainage of natural wetlands to provide land for building and agricultural use has been a further common human practice (as with the Somerset Levels) that has left surface water and excess river water with fewer places to go, leading to flooding.
The floods in the Severn Valley in 1998 were partly caused by human reasons. The flooding in this area has increased because of the housing developments on Greenfield sites. By this I mean that by concreting over the land humans have increased the rate of surface runoff and decreased the saturation levels of the ground. When surface runoff is high rainwater reaches the river faster. It would appear that the speed in which the water reached the river was too fast for the river to handle. The river filled up reaching bank-full discharge and then overflowing its banks onto the flood plain. The flood plain of the River Severn is built on, therefore, when the river floods it floods onto residential areas. With the building of these urban areas the amount of vegetation in the area surrounding the river was reduced, this affects the river two ways. It reduces the amount of interception, which in turn increases the speed of runoff into the river. This greatly affected many people lives, the flood led to at least 12 deaths, thousands of homes were marooned by floodwater, and experts estimated the total damage bill could exceed £100 million.
It becomes obvious that human activities, building and the need for sources of fresh water have had an impact on the natural way that water makes its way from the atmosphere to the sea through our rivers. This has almost certainly increased the potential for river flooding making it not such a natural hazard. Floods do and would occur even if humans didn’t build on and mess with floodplains, but the flood may not be as great or the flood may not even occur if the area was just left how nature made it to be.
Poor hazard management for example buildings in areas prone to earthquakes not being shock proof to withstand the shaking etc. If they were properly built and had the correct design and were prepared for disaster maybe less buildings would collapse killing less people. The earthquake may occur but if the buildings were made in order to prepare for this occurring then hopefully less people would be injured. People put themselves at risk by living in areas in which they know earthquakes may occur, often though due to a growing world population the need for houses and land is so huge they have to live and build in these areas in order to accommodate everyone.
Humans are also having an impact on atmospheric hazards with the increase in carbon dioxide levels causing global warming. Global warming is not only melting the ice caps but is also increasing the amount of rainfall and the number of storms we experience. The average UK temperature is expected to rise by 0.9 degrees by the year 2020. Current thinking suggests temperatures may become similar to those found in Southern France, twice as many days of temperature above 25 degrees and experiencing only eight nights of frost annually. Rainfall could be much lower leaving it prone to drought, only improved by intense thunderstorms, causing flash flooding but not alleviating the water stores. The likelihood of heatwaves will rise from once every 100 years to ever 3 by the year 2050. With these new extremes in temperature, extreme weather events could occur more often, such as an increase in average windspeeds, increasing the incidence of gales by about 30%. Humans are the main cause of global warming, in the USA, approximately 6.6 tons of are emitted per person every year. And emissions per person have increased about 3.4% between 1990 and 1997. Most of these emissions, about 82%, are from burning fossil fuels to generate electricity and power our cars. The remaining emissions are from methane from wastes in our landfills, raising livestock, natural gas pipelines, and coal, as well as from industrial chemicals and other sources. Humans can affect the emissions of about 4,800 pounds of carbon equivalent, or nearly 32% of the total emissions per person, by the choices you make in three areas of your life. These areas are the electricity we use in our homes, the waste we produce, and personal transportation. The other 68% of emissions are affected more by the types of industries in the U.S., the types of offices we use, how our food is grown, and other factors. Rising global temperatures are expected to raise sea level, and change precipitation and other local climate conditions. Changing regional climate could alter forests, crop yields, and water supplies. It could also affect human health, animals, and many types of ecosystems. As you can see the whole cause of global warming is based on human causes, thus meaning all the consequences of it and affects are not natural but are man caused making the hazards (flooding) not natural.
