Presentation on theme: "Mapping, Climate and Weather. Weather, mapping and our atmosphere What is the difference between weather and climate?"— Presentation transcript:
Mapping, Climate and Weather
Weather, mapping and our atmosphere What is the difference between weather and climate?
Weather, mapping and our atmosphere Weather is the combination of atmospheric elements, such as temperature, precipitation and humidity, that occur at a specific time and place.
Weather, mapping and our atmosphere Climate describes the same atmospheric conditions that have been averaged over a long period – often 30 years or more.
Weather, mapping and our atmosphere Around the planet, a wide range of weather occurs at any given time. Our weather is caused by different conditions in the Earths atmosphere.
Weather, mapping and our atmosphere The Earths atmosphere extends to around 1200 km above the surface. It is the first 50 km of the atmosphere that most affects our weather.
Weather, mapping and our atmosphere There are five layers to Earths atmosphere.
Weather, mapping and our atmosphere There are five layers to Earths atmosphere. Closest to Earths surface where things live. It contains about 50% of the air we breathe, and contains all the clouds we see and the weather we experience. From sea level up to about 16 km. Troposphere
Weather, mapping and our atmosphere There are five layers to Earths atmosphere. The air is thinner, because there are fewer gas particles than in the troposphere. Contains a further 40% of our air. No clouds, contains the ozone layer. From above 16 km to about 50 km. Stratosphere
Weather, mapping and our atmosphere There are five layers to Earths atmosphere. Gas particles become thinner and thinner in this layer. Shooting stars burn up here. From above 50 km to about 80 km. Mesosphere
Weather, mapping and our atmosphere There are five layers to Earths atmosphere. Fewer gas particles and very little effect on Earths air. From above 80 km to about 600 km. Thermosphere
Weather, mapping and our atmosphere There are five layers to Earths atmosphere. The very outer layer, with only a sprinkling of gas particles, many of which escape to outer space. Above 600 km to just over 1200 km. Exosphere
Heating places on Earth Solar radiation from the Sun is the main source of Earths energy. Without solar radiation, there would be no plant growth and no weather systems.
Heating places on Earth Different places on Earth receive different amounts of solar radiation – because of Earths tilt.
Heating places on Earth Fill in the gaps. An area on Earth at low latitudes (closer to the _________) receives more heat than the same area at high latitudes (closer to the _______). This is because the Suns rays hit places on Earth at _________ angles. The more direct the Suns rays, the ____ distance they travel through the atmosphere to hit the Earth, and the _____ heat is transmitted. more different Equator poles less different Equator poles less more
Heating places on Earth Where on Earth do the Suns rays hit most directly? Least directly?
What happens to solar radiation?
Heat is reflected from Earths surface, and some is trapped by greenhouse gases in the lower layers of the atmosphere. The main greenhouse gases are: water vapour carbon dioxide methane nitrous oxide ozone.
What happens to solar radiation? While these gases occur naturally, their levels have been increased by human activities. Does this situation need to be remedied? Why? Which human activities are thought to contribute most to raising the levels of greenhouse gases in the atmosphere?
What happens to solar radiation? This is how a greenhouse works for growing plants.
What happens to solar radiation? This is a simplified diagram of the Greenhouse Effect on Earth.
What happens to solar radiation? How do these diagrams explain the link between the Greenhouse Effect and Global Warming?
What happens to solar radiation? Global Warming refers to climate change – what does this mean?
What happens to solar radiation? What are the likely impacts of Global Warming on the natural environment, and on human activities like agriculture?
Climate graphs and maps Temperature and rainfall are the two most common measurements of weather conditions. Records are kept of these and other measurements, and they provide climatic data. Weather records and climatic data are kept on all continents, in many different places.
Climate graphs and maps This is climatic data for Cairns, in northern Queensland. Source: Bureau of Meteorology
Climate graphs and maps Mean is the average of a set of measurements. How is the mean daily temperature calculated? Answer – Calculate the half-way point between the mean maximum and minimum temperatures. How is mean monthly rainfall calculated? Answer – Take an average of the total rainfall received each month of the year, over an extended period of time (e.g. 30 years).
Climate graphs and maps Does Cairns have a smaller or larger range of temperatures over a year than cities in the southern states of Australia? Answer – Smaller
Climate graphs and maps Cairns has a tropical climate. Does this mean its temperatures are generally warm or cool? Answer – Warm
Climate graphs and maps Is its rainfall evenly spread or seasonal? Answer – Seasonal
Rainfall maps Rainfall maps use isohyet lines and colours to show the ranges of average precipitation in different areas. An isohyet is a line on a map that connects places with equal precipitation. Source: Bureau of Meteorology
Rainfall maps Name as many forms of precipitation as you can. Answer – Rain, hail, snow, sleet, mist Source: Bureau of Meteorology
Rainfall maps Why arent things such as dew, frost and fog classified as forms of precipitation? Source: Bureau of Meteorology
Rainfall maps What are the average rainfall ranges used on this map? Source: Bureau of Meteorology
Rainfall maps Which parts of Australia receive the most rain? Source: Bureau of Meteorology
Rainfall maps Which parts of Australia receive the least rain? Source: Bureau of Meteorology
Rainfall maps Describe the pattern of annual rainfall in Australia. Source: Bureau of Meteorology
Temperature maps Temperature maps use isotherm lines and colours to show the ranges of average temperature in different areas. Source: Bureau of Meteorology
Temperature maps An isotherm is a line on a map that connects places of equal temperature. It can be indicated by a change in colour. Source: Bureau of Meteorology
Temperature maps Why is it informative to have two temperature maps for Australia – one showing January temperatures and one showing July temperatures? Source: Bureau of Meteorology
Temperature maps Which parts of Australia are hottest in January? Source: Bureau of Meteorology
Temperature maps Suggest reasons for this spread of temperatures. Source: Bureau of Meteorology
Temperature maps Which parts of Australia have the highest temperatures in July? Source: Bureau of Meteorology
Temperature maps Describe the pattern of temperatures in July, from northern Australia to southern Australia. Source: Bureau of Meteorology
Weather forecasting Maps of expected weather conditions appear daily on TV, in newspapers and on the Internet. This is one type of weather forecasting map: It summarises expected weather conditions – temperature and rainfall.
Weather forecasting There are two figures shown for each city and town on the map – what do these mean? Answer – They show the minimum and maximum temperatures for each city or town.
Weather forecasting Which areas have the highest probability of rain? Answer – The areas shaded the darkest green
Weather forecasting What does a lack of shading mean, regarding the probability of rain? Answer – That there is little or no possibility of rain (less than 10%)
Weather forecasting Which three cities or towns are expected to have the lowest minimum temperatures? Answer – Canberra, Hobart, Adelaide
Weather forecasting Which four cities or towns are expected to have the highest minimum temperatures? Answer – Broome, Darwin, Mt Isa, Rockhampton
Synoptic weather maps A synoptic chart shows the main elements of the weather system at a particular time, such as highs, lows and cold fronts. Readings of atmospheric measurements are taken at ground level.
Synoptic weather maps High is a short way of describing a high pressure cell, where the air pressure increases towards the centre. Cold front is the boundary where a mass of cold air is replacing warm air, causing a sharp change in temperature. Low is a short way of describing a low pressure cell, where the air pressure decreases towards the centre. Isobars are lines on a synoptic weather map that join places of equal air pressure.
Synoptic weather maps Can you see different high and low pressure systems on this synoptic chart? Where are they? What other information is shown by the symbols on this synoptic chart?
Climate change Many scientists believe that global warming is Earths greatest environmental threat. The global trend shows increasing temperatures, which could be caused by the Greenhouse Effect.
Climate change What does this graph show? Answer – The relationship between temperatures and concentrations of carbon dioxide in the atmosphere over an extended period Source: World Data Center for Paleoclimatology
Climate change Fill in the gaps. This graph shows that variations in ____________ have occurred consistently over the past __________ years. There is a distinct relationship between temperature and levels of _______________ gas in the atmosphere carbon dioxide temperature carbon dioxide
Climate change Fill in the gaps. Over the past couple of centuries, carbon dioxide levels in the ____________ have been greater than ever before. This is because in that time __________ activity (particularly the use of ________ fuels) has resulted in many more emissions. fossil human atmosphere human fossil
Climate change Fill in the gaps. This graph shows that the __________ averaged surface temperature has steadily ___________ since In that time, _______________ levels have also increased. globally increased carbon dioxide increased globally carbon dioxide Source: World Data Center for Paleoclimatology
Climate change discussion In what ways are these three groups responsible for climate change? individuals governments business and industry In what ways could the three groups above contribute to resolving the issues of climate change? Do people in third-world countries have the same responsibilities for climate change as those in first-world countries? Why?