Unit 2 Climate And Change Flashcards
How do ice cores provide us with evidence of past climates?
Layer upon layer, snow builds up and eventually turns into ice. As a result, microscopic air bubbles become trapped. When we melt the ice cores we can see the concentration of certain gasses such as CO2. A higher amount of CO2 from a past climate tells us that the temperature must have been fairly warm
How does pollen analysis provide us with evidence about past climates?
The study of pollen preserved in sediment can show the vegetation of a particular area. Therefore we can learn which plants colonised the UK in the past. If these plants were suited to hot/cold conditions, we can then tell what the climate must have been like at this time
How do tree rings provide us with evidence about past climates?
Each ring in a tree represents the growth of the tree per year. The width in each ring reveals the growth rate for an individual ring per year. During warmer years, the trees grow more therefore the gaps in between each rings increase
BIGGER RINGS=MORE CO2=WARMER TEMPERATURES
How does glacier retreat provide us with evidence of past climates
Glaciers around the world have exhibited a general retreat up the mountains in the past 200-250 years. The higher up the mountain, the colder it gets. As the bottom of the mountain is warmer and if there is no ice present, this would suggest that the ice has melted meaning the climate at the time must have been warm.
How do writings/artwork provide us with evidence of past climates?
Weather diaries have recorded past temperatures which gives us a flavour of past climates e.g. The frozen river Thames. However, these can be unreliable as often people can lie or over exaggerate, or give false temperature readings. I
How does the eruption theory show causes of climate change?
When volcanoes erupt, they release huge amounts of ash and sulphur dioxide. The same applies when asteroids hit the earth. The ash and sulphur seized then gets released on bro the atmosphere, causing a ‘blanket’ effect which blocks out the sunlight this resulting in a cooler average temperature for the planet. An example of this is the eruption of Mount Pinatubo. 17 million tonnes of sulphur dioxide was released into the atmosphere reducing sunlight by 10% and cooling the planet by an average of 0.5 degrees for a whole year.
How are sunspots causes of climate change?
Sunspots of the sun provide evidence of climate change. The more sunspots there are, the more active the sun is meaning there is more solar energy being fired towards the earth. Therefore, we can infer that the more sunspots there are, the greater the average temperature will be at that given time.
Name 3 ways in which the orbit and axis of the earth can affect global temperatures
–The earths orbit is sometimes circular and sometimes changes to a more elliptic orbit
–The earths axis tilts between 22 and 24.5 degrees
–The earth’s axis wobbles, like a spinning top about to fall over
How does the orbit of the earth change the temperature of the earth?
Changed from a circular to an oval (elliptic) orbit can affect the amount of sunlight the earth receives. It takes 100,000 years for the Earth’s orbit to change from being circular to an ellipse and back again
How does the tilting of the the earths axis affect global temperatures?
The earth’s axis tilts. Sometimes it is more upright, and sometimes it is more on its side. When the earth is more upright, it relieves a greater amount of energy from the sun and experiences higher temperatures.
Name 5 pieces of evidence about past climates
Ice cores Pollen analysis Tree rings Glacier retreat Artworks/writings
How did the dinosaurs die out?
- Sulfur dioxide released into the stratosphere
- Blocks sun
- Cools planet
- Plant can’t grow
- Affects food chain
Name the 5 air masses
- NW polar maritime- wet cold air brings cold showery whether
- N arctic maritime- wet cold air snow in winter
- NE polar continental- hot air dry summers cold air brings dry summers
- SE tropical continental- hot summer
- SW tropical- warm moist rain and mild weather
