1. The Earth Climate

2. Contents 1 Definition 2 Climate classification 3 Record 3.1 Modern
3.2 Paleoclimatology
4 Climate change
4.1 Climate models
5 References

3. What is Climate?
Climate = the average and variations of weather over a long period of time (~30 years) but other periods may be used depending on the purpose. Climate also includes statistics other than the average, such as the magnitudes of day-to-day or year-to-year variations.
Therefore, climate is “the average and variations of weather over long periods of time”.
Above: Global average for atmospheric water vapor.

4. The Intergovernmental Panel on Climate Change (IPCC) glossary definition is as follows:
Climate in a narrow sense is usually defined as the "average weather," or more rigorously, as the statistical description in terms of the mean and variability of relevant quantities over a period ranging from months to thousands or millions of years. The classical period is 30 years, as defined by the World Meteorological Organization (WMO). These quantities are most often surface variables such as temperature, precipitation, and wind. Climate in a wider sense is the state, including a statistical description, of the climate system.[5]

5. The difference between climate and weather is usefully summarized by the popular phrase "Climate is what you expect, weather is what you get."[6]

6. Climate classification
There are several ways to classify climates into similar regimes. Originally, climes were defined in Ancient Greece to describe the weather depending upon a location's latitude. Modern climate classification methods can be broadly divided into genetic methods, which focus on the causes of climate, and empiric methods, which focus on the effects of climate. Examples of genetic classification include methods based on the relative frequency of different air mass types or locations within synoptic weather disturbances. Examples of empiric classifications include climate zones defined by plant hardiness,[10] evapotranspiration,[11] or more generally theKöppen climate classification which was originally designed to identify the climates associated with certain biomes

7. Bergeron and Spatial Synoptic
The simplest classification is that involving air masses. The Bergeron classification is the most widely accepted form of air mass classification. Based upon the Bergeron classification scheme is the Spatial Synoptic Classification system (SSC). There are six categories within the SSC scheme: Dry Polar (similar to continental polar), Dry Moderate (similar to maritime superior), Dry Tropical (similar to continental tropical), Moist Polar (similar to maritime polar), Moist Moderate (a hybrid between maritime polar and maritime tropical), and Moist Tropical (similar to maritime tropical, maritime monsoon, or maritime equatorial).[14]

8. The Köppen Climate Classification System is the most widely used for classifying the world's climates. Most classification systems used today are based on the one introduced in 1900 by the Russian-German climatologist Wladimir Köppen. Köppen divided the Earth's surface into climatic regions that generally coincided with world patterns of vegetation and soils.

9. Köppen climate classification
The Köppen system recognizes five major climate types based on the annual and monthly averages of temperature and precipitation. Each type is designated by a capital letter. A - Moist Tropical Climates are known for their high temperatures year round and for their large amount of year round rain. B - Dry Climates are characterized by little rain and a huge daily temperature range. Two subgroups, S - semiarid or steppe, and W - arid or desert, are used with the B climates. C - In Humid Middle Latitude Climates land/water differences play a large part. These climates have warm, dry summers and cool, wet winters. D - Continental Climates can be found in the interior regions of large land masses. Total precipitation is not very high and seasonal temperatures vary widely. E - Cold Climates describe this climate type perfectly.

11. Climate Change, Global Warming… …Shilina Anastasia Logunov Andrew 9B
Global Climate Change
Climate Change, Global Warming…
…Shilina Anastasia
Logunov Andrew 9B

12. What is Weather?
Weather = all natural phenonmena within the atmosphere at a given time (hours to days)

13. What is Science? Science is the search for knowledge.
It is the testing of different hypotheses in the attempt to work out how and why things are as they are.
For example, by answering scientific questions we can map out the phases of the moon (left) and track the effects of the changing seasons (right).
The extent of snowfall as the seasons progress from Summer into Winter and then back to Summer again.
The lunar cycle

14. What is Climate Change?
Records change over decades to millions of years
Climate change refers to the variation in the Earth's global climate or in regional climates over time.
It describes changes in the variability or average state of the atmosphere over time scales ranging from decades to millions of years.
These changes can be caused by processes internal to the Earth, external forces (e.g. variations in sunlight intensity) or, more recently, human activities.

15. The Climate System Land Ice Oceans Atmosphere Biosphere
The Earth has many different systems that interact with each other in different ways.
Ice
Biosphere
The climate includes interaction between all areas on the surface of the Earth and in the atmosphere.
For example, water is evaporated from the ocean to form water vapor clouds in the atmosphere. The wind can then carry these clouds over the land where the water falls as rain or snow. Eventually the water may return to the ocean via rivers etc.
Also, the biosphere the living plants and animals, live in and utilize the land, sea and sky - so you can see how everything is connected.
Land

16. Modern Climate Systems
Atmospheric circulation
Sunlight
Atmospheric circulation is the large-scale movement of air, and the means (together with the ocean circulation, which will be discussed next) by which heat is distributed on the surface of the Earth.
The warm air found around the equator (see figure) can mix with cold air from the poles.
This air movement forms convection cells and jet streams (fast moving air currents between areas of great temperature differences)
The large-scale structure of the atmospheric circulation varies from year to year, but the basic structure remains fairly constant….see next slide

17. Modern Climate Systems
Ocean circulation
Sinking cool water, rising warm water and wind help to form global ocean current systems.
Oceanic circulation is the second way heat is distributed over the globe. This is done by surface currents and also deep global currents.
Surface currents:
The ultimate reason for the world's surface ocean currents is the sun. The heating of the earth by the sun has produced semi-permanent pressure centers near the surface, as we saw in the last slide. When wind blows over the ocean around these pressure centers, surface waves are generated by transferring some of the wind's energy, in the form of momentum, from the air to the water. This constant push on the surface of the ocean is the force that forms the surface currents.
These can travel great distances. For example, in January 1992, a container ship near the International Date Line (Pacific Ocean), headed to Tacoma, Washington from Hong Kong, lost 12 containers during severe storm conditions. One of these containers held a shipment of 29,000 bathtub toys. Ten months later, the first of these plastic toys began to wash up onto the coast of Alaska. Driven by the wind and ocean currents, these toys continue to wash ashore during the next several years and some even drifted into the Atlantic Ocean.
Deep currents:
There is also global circulation which extends to the depths of the sea called the Great Ocean Conveyor. Also called the thermohaline circulation, as it is driven by differences in the density of the sea water which is controlled by temperature (thermal) and salinity (haline).
In the northern Atlantic Ocean, as water flows north it cools considerably increasing its density. As it cools to the freezing point, sea ice forms with the "salts" extracted from the frozen water making the water below more dense. The very salty water sinks to the ocean floor.
It is not static, but a slowly southward flowing current. The route of the deep water flow is through the Atlantic Basin around South Africa and into the Indian Ocean and on past Australia into the Pacific Ocean Basin.
If the water is sinking in the North Atlantic Ocean then it must rise somewhere else. This upwelling is relatively widepsread. However, water samples taken around the world indicate that most of the upwelling takes place in the North Pacific Ocean.
It is estimated that once the water sinks in the North Atlantic Ocean that it takes 1,000-1,200 years before that deep, salty bottom water rises to the upper levels of the ocean.
The Great Ocean Conveyor

18. What is the Greenhouse Effect?
The Earth receives energy from the Sun in the form of radiation.
The Earth reflects about 30% of the incoming solar radiation. The remaining 70% is absorbed, warming the land, atmosphere and oceans.
For the Earth's temperature to be in equilibrium so that the Earth does not rapidly heat or cool, this absorbed solar radiation must be very nearly balanced by energy radiated back to space in the infrared wavelengths.
The figure on the left shows the absorption bands in the Earth's atmosphere (middle panel), I.e. the wavelength spectrum (UV, IR, visible light) that is absorbed by the atmosphere, and the effect that this has on both solar radiation (energy from the sun) and upgoing thermal radiation (energy reflected from the Earth) (top panel).
Individual absorption spectrum for major greenhouse gases are also shown.
You can see that high amounts of UV and IR wavelengths from the sun are absorbed by the atmosphere, whereas much of the visible light spectrum passes through (allowing us to see!). Of the up-going thermal radiation (blue) a budget of IR wavelengths pass through the atmosphere to be lost to space.
The figure on the right is a simplified, schematic representation of the flows of energy between space, the atmosphere, and the Earth's surface, showing how these flows combine to trap heat near the surface and create the greenhouse effect.
Energy exchanges are expressed in watts per square meter (W/m2); values from Kiehl and Trenberth (1997).
The sun provides an annual average of ~235 W/m2 of energy to the Earth’s surface. If this were the total heat received at the surface, then we would be expect to have an average global temperature of -18°C. Instead, the Earth's atmosphere recycles heat coming from the surface and delivers an additional 324 W/m2, which results in an average surface temperature of roughly +14 ° C.
Of the surface heat captured by the atmosphere, more than 75% can be attributed to the action of greenhouse gases (carbon dioxide, methane, nitrous oxide etc.) that absorb thermal radiation (the up-going energy emitted by the Earth's surface).
The atmosphere in turn transfers the energy it receives both into space (38%) and back to the Earth's surface (62%), where the amount transferred in each direction depends on the thermal and density structure of the atmosphere.
This process by which energy is recycled in the atmosphere to warm the Earth's surface is known as the greenhouse effect and is an essential piece of Earth's climate.
Under stable conditions, the total amount of energy entering the system from solar radiation will be exactly the same as the amount being radiated into space, thus allowing the Earth maintain a constant average temperature over time. However, recent measurements indicate that the Earth is presently absorbing W/m2 more than it emits into space (Hansen et al. 2005). This increase, associated with global warming, is believed to have been caused by the recent increase in greenhouse gas concentrations.
References:
Kiehl, J. T. and Trenberth, K. E. (1997). "Earth's Annual Global Mean Energy Budget". Bulletin of the American Meteorological Association 78:
Hansen, J., et al. (2005). "Earth's Energy Imbalance: Confirmation and Implications". Science 308 (5727):
cc. Robert A. Rohde (Global Warming Art)
The temperature of the Earth depends on the amount of energy we receive from the sun versus the amount of energy lost back out to space.
cc. Robert A. Rohde (Global Warming Art)

19. Is the Climate Changing?
In the following section we will discuss the past and current trends in climate change and use these models to look towards the future.

20. What are the current climate trends?
If you put the data on the last slide onto a map to plot where the temperature changes are occurring, you get the above figure.
Note: Some parts of Antarctica have become colder. Whereas the majority of the northern hemisphere is warmer. On average the UK has become 1°C hotter
cc. Robert A. Rohde

21. Future predictions…
Based on no changes in emissions (“business as usual”)
The UK would be 2-3.5°C hotter on average.
This figure shows the predicted distribution of temperature change due to global warming from the Hadley Centre HadCM3 climate model.
These changes are based on the IS92a ("business as usual") projections of carbon dioxide and other greenhouse gas emissions during the next century, and essentially assume normal levels of economic growth and no significant steps are taken to combat global greenhouse gas emissions.
The plotted colors show predicted surface temperature changes expressed as the average prediction for relative to the model's baseline temperatures in
The average change is 3.0°C, placing this model on the lower half of the Intergovernmental Panel on Climate Change's °C predicted climate change from 1990 to 2100.
As can be expected from their lower specific heat, continents are expected to warm more rapidly than oceans with an average of 4.2°C and 2.5°C in this model respectively. The lowest predicted warming is 0.55°C south of South America and the highest is 9.2°C in the Arctic Ocean (points exceeding 8°C are plotted as black).
Note the large increase in temperature over the South American continent. A result of the loss of the Brazilian rainforest.
cc. Robert A. Rohde

22. The way to solve the problem.
Recycle
Turn off lights
Low energy light bulbs
Shorter showers
Recycle «grey»water
Install solar panels
Walk or ride instead of taking a vehicle

23. References
Jump up^ AR4 SYR Synthesis Report Annexes. Ipcc.ch. Retrieved on
Jump up^ C. W. Thornthwaite (1948). "An Approach Toward a Rational Classification of Climate". Geographical Review 38 (1): 55–94.doi: /  JSTOR 
Jump up^ "Climate". Glossary of Meteorology. American Meteorological Society. Retrieved 
Jump up^ "Climate averages". Met Office. Retrieved 
Jump up^ Intergovernmental Panel on Climate Change. Appendix I: Glossary. Retrieved on
Jump up^ National Weather Service Office Tucson, Arizona. Main page.Retrieved on
Jump up^ Stefan Rahmstorf The Thermohaline Ocean Circulation: A Brief Fact Sheet. Retrieved on