A sustained period of low precipitation can be beneficial to plants in the sense that artificially watering plants is easy and concentrated sunlight can lead to rapid crop growth. However, like in 1977 when an anti-cyclone lasted 2months, water restrictions and bans could be placed on agriculture and industry also leading to destruction of crops and manufacturing output, which has a negative economic impact on farmers and industrial workers. It therefore important that a reliable source of water is available e.g. in London an aquifer underneath the city is used as a vast water reserve, which has proven vital to increasing water supplies when they are reduced.
Blocking anti-cyclones also occur during winter, which also causes challenges. During the day, temperatures rise, but at night temperatures fall dramatically, which can threaten elderly and young, who can be caught off guard. As a result, challenges can be ensuring stocks of cold medicine is available a pharmacists to ensuring the central heating is working in all homes due to threat of hypothermia, which is dangerous.
The cold temperatures at night can also lead to poor driving conditions because if there is some precipitation, roads can ice over making the risk of accident greater. As a result, road authorities have to ensure that grit is laid, ambulances are prepared and car breakdown services are notified, as cold conditions do not suit the working of engines.
In conclusion, it is evident that blocking anti-cyclones can negatively affect all aspects of life and therefore must be prepared for.
3. Study Resource 3
- Describe how annual rainfall varies across Africa. (5)
The graphs shows that Libreville experiences two peaks in precipitation reaching 350mm to 375mm in May and November and then a period of low precipitation during summer e.g. 0mm in June. It is located on the equator, which suggests that there is much convectional and transpiration precipitation in the region.
The countries that experience least precipitation are Mogador (215mm per annum), Timbuktu (240mm) and Khartoum (115mm). They are located in northern Africa Khartoum and Timbuktu within the Tropics of Cancer and Mogador just outside.
In Southern regions of Africa Luanda, Bulawayo and Alavi experience low precipitation also, but slightly more than the northern settlements. All experience similar changes in precipitation with the summer months receiving the least precipitation and the winter and colder months receiving most.
- Explain this variation (10)
Look at diagram 1
- For one named area, examine the impacts of the monsoon (10)
The Monsoons affect a wide variety of people in West Africa. The Monsoon comes in both dry and wet spells due to the reversal of winds, which bring wet winds from the tropical maritime direction or dry winds from the polar continental direction.
Wet monsoons affects people both socially and economically. A major problem for LEDCs in Africa is the spread of disease and the introduction of a wet monsoon allow them to spread more quickly especially waterborne diseases such as malaria and cholera. This has a social affect on people because many people die from these illnesses e.g. in 2000, 700,000 Africans died from Malaria alone. This has an affect also upon the economy of the region because if people are ill there are less people working and therefore people have reduced incomes resulting in economic hardships in the region.
Landslides are also a common occurrence in countries that experience heavy wet monsoons. The saturation of terrain with varying topography and relief results in the creation of slip planes. This threatens in particular those people living in shanty towns commonly found on desirable land such as hillsides. Landslides have catastrophic impacts killing many and destroying houses. People are socially affected because they lose their families and friends and economically also because they will have to invest in new building materials to re-construct their homes.
Flooding is a common occurrence during wet monsoons that affect the environment, and people socially and economically. Flooding in Bangladesh for example has claimed the lives of hundreds of thousands and therefore has the potential to do so in West Africa. Flooding can destroy habitats of animals and settlements of people having negative social and environmental affects. The water also enables further the spread of disease as sewerage systems are over run by water and therefore cannot filter that is harmful leading to unsanitary conditions in the region. Crops are also destroyed resulting in a loss of income for farmers, which is an economic impact and also socially affects the region because there is a reduced supply of food resulting in famine.
The environment is also affected by wet monsoon. Plants have adapted by growing leaves that channel water from their surface so their pours are not blocked. Some have grown deep roots so that heavy floods do not wash them and also thick trunks to increase this resilience and also to store water during the dryer months.
Talking about dryer months, the dry monsoon also negatively affects the people. Although, the wet monsoon can bring many negatives it brings an important source of water to the region for domestic and agricultural use. If the precipitation level is low then less crops are able to be grown and less water is available to be drunk resulting in negative social and economic impacts. The high intensity of sunlight and heat also results in land becoming impermeable and therefore, difficult to irrigate or farm resulting in reduced space for farmers to grow crops resulting in a negative economic impact.
Plants also rely on a good source of water and therefore, some have evolved so that they can survive for long periods without water. However, many plants have not and therefore, die due to lack of water. Forest fires are also common in hot conditions which kill plant and wildlife, as well as threaten settlements e.g. Sydney in 2002. Fires can destroy and harm all aspects of life e.g. killing people, burning settlements and crops and therefore, this is another negative impact of the dry monsoon.
In conclusion, the monsoons in West Africa are something not to be desired, as many negatives arise from their arrival.
4.
- Draw an annotated diagram to explain global warming (5)
Look at diagram 2
- Examine the view that “global warming is not human induced”. (10)
The general scientific feeling amongst scientists is that global warming originates from humans. We create harmful emissions known as greenhouse gases produced by deforestation, industry and vehicles e.g. CO2 and methane that work to trap the heat that comes from the sun, hence gradually increasing the earth’s temperature. However, there is much debate over whether global warming is not human induced and is just a natural cycle of the earth’s life that is too complex for us to understand at this current time. The huge range of differing opinions that will be explained emphasises that this is a seriously contest issue that no one seriously can claim they have the correct answer.
Firstly, solar activity can greatly affect the global temperatures. Sun spots on the sun release massive amounts of heat and if directed at the earth can result in small increases in temperatures. Although analysis of the sun is at a high level and sunspots are easier to find than before, sunspots occur frequently and therefore, they are unsure on their affects.
Solar energy is also affected by volcanic activity. Millions of years ago the earth was unstable and therefore experienced frequent volcanoes. The dust and ash that arose from the earth caused reductions in temperatures due to the shadow created by them over the earth. At present, the level of volcanic activity is significantly less and therefore, this results less dust and ash blocking the sun’s heat. Thus enabling the solar energy of the sun to gradually heat the earth.
Continuing with the theme of solar activity, the amount of it causes changes in ice cover across the poles of the planet. This is known as the albedo effect. It is a theory that explores the idea that when the earth was colder millions of years ago or even 40,000 years ago was the last minor ice age, the amount of ice cover was large reaching north America for example. As a result, the sunrays that came to earth were reflected meaning the earth did not absorb much heat and remained cold. However, now that earth has moved away from the minor ice age temperatures have begun to increase meaning the albedo effect has little impact on maintaining low temperatures.
The Milankovitch Cycle is also a far-fetched theory, but it could have an effect on increasing global temperatures. Every 4,000 years or more the earth’s axis tilts. Therefore, the concentration of sunlight on different parts of the world alters. It is possible that the sun is concentrating more rays on the North Pole than it did in the past reducing the albedo effect and therefore, increasing global temperatures.
Finally, ocean currents also have caused changes in the earth’s climate. El Nino and other ocean current phenomenon have caused increases in global temperatures in specific parts of the world. It would seem that El Nino and other ocean currents are becoming more severe in the difference between warm and cold currents resulting in extreme weather and also warmer global temperatures.
- With reference to one named country, examine the “challenges” that global warming may cause (10)
Global warming is believed to be a major global challenging and will continue to increase in difficulty in the future as global temperatures increase resulting the thermal expansion of the sea and changes in climatic conditions across the world. Britain is one of those countries that must be weary of the dangers that global warming can bring. With low-lying land, slight increases in temperatures will result in loss of important nature reservations particularly the Norfolk and settlements e.g. London. There will also be changes in climate bringing changes in society and the economy.
A rise in sea level firstly will mean that the government will have to increase their investment into coastal defence. This will result in the government having less money to spend on the population and other problems affecting the country. This could prove to have many negative social and economic consequences for the future not just for the public e.g. possibly increased taxes, but also for the government e.g. reduction in NHS resulting in an unfavourable electorate.
Increase in sea temperatures will also threaten many important nature reserves. The Norfolk Broads has a massive environmental and economic value to Britain. It is home to many rare fresh water species e.g. Bean Geese and as a result if the Broads were to be flooded it would become inhabitable for them and they would leave. It is also an important source of income for many people working on or linked to the broads e.g. boat companies. The broads receive 2million visitors a year and if they were to be lost unemployment would rise massively, which would negatively affect society and the economy.
Low-lying settlements will also be affected e.g. London, which is one of the world’s financial centres. If large areas of this city were to be lost then many people working in the service sector will lose their jobs resulting in unemployment thus economic hardship for those unemployed having negative social consequences e.g. loss of self-esteem etc. The government has attempted to tackle the problem with the construction of the Thames Barrier, which was built in the 1980s. However, this is not a permanent solution, as many other regions will not be protected.
Changes in climate will also result from global warming. It is predicted that England’s climate will become more of a Mediterranean like environment. This will result in new crops being able to be grown, which is economically beneficial to the country. However, a reduction in precipitation is also a likely result and therefore, this might affect the capacity of crops that can be produced, which should be addressed.
Warmer sea temperatures off the coasts could also result in the temperatures being more sustainable for fish that prefer warmer environments and therefore, enable the British industry to expand. However, it could also result as a disadvantage because deeper waters mean fish are able to live deeper making fishing harder and therefore, could actually cause a reduction in the available supply of fish, which would be an economic disadvantage.
The changes in the British climate will also bring an increase in the severity and degree of weather. Storms, floods, droughts are all likely consequences of global warming. Weather will become unpredictable and possibly dangerous to the population, economy and environment. El Nino is becoming more frequent, which has been known to effect completely obscure places nowhere near Australasia or South America e.g. the Rocky Mountains in North America exprienced sever depletion of snow in 1992, as a result of El Nino. Therefore, it will be difficult to predict what the likely consequences will be for the British isles.
In Conclusion, there is a mixture of possible consequences for the UK. Whether they be beneficial or detrimental to the country, the government must consider the consequences in order to be fully prepared for the affects of global warming.
GEORGE RYAN
