chap1: w&c gw2 Flashcards
how volcanic eruption can cause climate change
During a volcanic eruption, it releases a large amount of materials and gases such as carbon dioxide, sulphur dioxide, dust and ash into the atmosphere. For example, Mount Pinatubo, Phillipines in 1991 releases 17 million tonnes of sulpher dioxide into the atmosphere. As the particles accumulate, solar energy is reflected back into space. This will result in global dimming which is the reduction in amount of sunlight reaching the surface of earth. This causes cooling influence on global and regional temperature. Cool effect stops when dusts and ash are settled.
what is greenhouse effect?
Greenhouse effect is a natural process which is important for life on earth as it keeps the earth warm and habitable. Greenhouse gases include carbon dioxide, water vapour, methane and many more. On earth, it helps with the growth of plants even during winter. Thus, greenhouse is common in countries experiencing cooler temperature climate such as United States. Similarly, the earth’s surface acts like greenhouse as it protects earth from being too cold
describe the processes that help to keep the earth warm
Sun’s energy entering the earth’s surface is called incoming shortwave radiation. It passes through the atmosphere and enters the earth’s surface. However, some of the shortwave radiation gets reflected by both the atmosphere and earth’s surface. Most of shortwave radiation gets absorbed by the earth’s surface and is heated up. The warm surface emits incoming longwave solar radiation. The greenhouse gases then absorbs the longwave radiation, warming the atmosphere.
what is enhanced greenhouse effect?
Enhanced greenhouse effect is the increase in amount of greenhouse gases in the atmosphere. This is caused by human activities. Human activities causes greenhouse gases to be released at a greater rate than natural emissions of greenhouse gases. The increase in greenhouse gases can causing an increase in global temperature.
how deforestation can lead to the enhanced greenhouse effect
Deforestation refers to the loss of forest due to the removal of trees in forested areas. The trees are cut down for purposes such as production of paper and furniture, and create land for human activities. Trees absorbs billion tonnes of carbon dioxide every year through photosynthesis and release oxygen into the atmosphere. Due to deforstation, there are fewer trees to absorb carbon dioxide, leading to an increase in amount of carbon dioxide. Similarly, soil is rich is carbon dioxide. When trees are removed, it is more exposed to sunlight and oxygen which causes soil to oxidise and releases more carbon dioxide. Thus, the overall increase in the amount of carbon dioxide leads to an overall increase in heat trapped by greenhouse gases in the atmosphere. This leads to enhanced greenhouse effect. Places facing deforestation is Kalimantan, Amazon Forest
how urbanisation can lead to the enhanced greenhouse effect
Urbanisation refers to people living in urban areas such as towns and cities. As more people move into cities, there is a greater demand for human activities such as cooking, lighting, heating and cooling. To produce energy, a large amount of fossil fuels are burnt release greenhouse gases. The high concentration of vehicles such as cars amd buses also contributes to greenhouse effect. Constructing infrastructure and producing construction materials also releases greenhouse gas. Thus, an overall increase in amount of carbon dioxide causes an overall increase in heat trapped in greenhouse gases in atmosphere. This will lead to enhanced greenhouse effect.
explain the role greenhouse gases play in keeping earth warm
Solar radiation entering the surface of earth is called incoming shortwave radiation. Most of the shortwave radiation is absorbed into the earth’s surface and gets heated up. The warmed earth’s surface emits incoming longwave radiation. Greenhouse gases absorbs longwave radiation, keeping the earth warm
sea level rise
Refers to the increase in sea’s surface between high tide and low tide. This is caused by the melting of glaciers and expansion of water due to high temperatures. Natural climate change causes sea level to flactuate over million of years. Over 600 million people live in areas that are less than 10metres above sea level. Two-third of the world’s largest cities are located in coastal areas. This areas will be at risk of flooding. Flooding causes loss of land for human activities. For example, Majuro Atoll will lose 80% of its land if sea level rises by half a metre.
spread of insect-borne diseases
Insects prefer living in conditions where temperature and rainfalls are high. Due to the enhanced greenhouse effect, many areas in the world are experiencing these weather conditions. As a result, this will cause more insects to breed and many carry insect-borne diseases. Some mosquitoes such as Aedes mosquito, carry diseases such as dengue which causes people to have flu and fever. This will negatively impact the economy as people who are ill will need to stay away from work and productivity will be reduced.
what are the impacts of climate change?
rising sea level
spread of insect-borne diseases
describe a sampling method that could be used
random sampling
students generate random numbers to pick samples such as through random number table
advantage: everyone has equal chances of being picked, used to obtain large sample population
disadvantage: may not represent the actual population structure
benefits of conducting pilot survey
check whether their interview questions are appropriate
check whether they have sufficient sites
how land breeze is formed
At night, water bodies lose heat at a slower rate than land, causing higher temperature. Warm air over the sea heats up, expands and rises, creating an area of lower pressure. Air cools and shinks over land, causing a higher pressure. Air moves from land to sea, causing land breeze
characteristics of equatorial climate
High precipitation all year round, higher temperature all year round, small annual temperature range
instrument use to obtain wind direction and how to ensure their data is as accurate as possible
wind vane
students can place wind vane in an open area where the wind is directly blowing at. They use a compass to match the wind vane and ensure it is both facing north. Record the direction wind vane is pointing at. That is where wind is coming from.
