cause and description

Question 1

Natural

Answer 1

There are a number of natural causes of glaciers and ice sheets(warming) and some of the points listed below can also lead to cooling of places in some cases

Question 2

Variations in solar energy

Answer 2

The elliptical orbit of the earth is subject to 3 independent cycles of change that alter the distance between the earth and sun every 100,000 years.

natural climatic cycles of global glaciation and warming.

Question 3

Oceanic circulation changes

Answer 3

The direction of ocean currents have changed regularly in recent geological times and many continents have experienced changed climats as a result.

Thermohaline (part of oceanic) circulation transfers heat throughout the oceans, and past changes to these currents have caused major shifts in global climate.

El Nino - brings drought
La nina - storm system - brings floods and rains
Cross specific currents

Question 4

Volcanic activity

Answer 4

This can cause significant amounts of dust and gasses to be injected into the atmosphere. This in turn can lead to both warming and cooling events for the climate.
atmospheric cooling

The ejection of greenhouse gasses from volcanoes can lead to very minor atmospheric warming.

Question 5

Plate tectonics

Answer 5

The redistribution of land masses has long been caused by tectonic plates.

led to movement of continents and changed oceanic and atmospheric circulation patterns.

Question 6

Human

Answer 6

Since the beginning of the industrial revolution, people have significantly changed the appearance of the Earth’s surface.

Question 7

Alteration of the composition of gasses in the atmosphere

Answer 7

Industrialisation has meant the increased injection of greenhouse gasses such as carbon dioxide, methane gas into the atmosphere.

Methane release from vast areas of thawing arctic permafrost and from lake-bottom sediments is becoming a major issue

Question 8

Alteration of landscapes

Answer 8

Considerable changes in solar radiation absorption are created by the construction of hard surfaces in cities, the clearance of forests for agriculture and many other modifications to the landscape.

These landscape changes lead to the extension of heat near the earth’s surface, enhancing the greenhouse effect.

Question 9

Direct addition of heat to the atmosphere

Answer 9

Burning fossil fuels, for electricity production, transportation (planes, cars, ships etc),

Burning fossil fuels such as coal, oil and natural gas and the clearing and burning of forests contributes to most of the estimated increase in carbon dioxide.

Carbon dioxide also increases plant growth and this can lower land surface albedo
albedo - absorption of heat and radiation.