Climate Review

What are some of the greenhouse gases, and where did they come from?

Carbon Dioxide - CO2. Produced when organic matter (trees/fossil fuels which are non-renewable energy) is burned. Sources - living organisms, decomposition/burning of organic matter, deforestation, erosion of carbonate rocks, volcanoes. Methane - CH4. Present in natural gas, produced when organic matter decomposes without oxygen (swamps, oceans, digestive systems, landfills) Nitrous Oxide - N2O. Made naturally in oceans and rain forests, also in nylon production, the burning of organic matter and fertilizers. Sulfur Hexaflouride - SF6. This gas is completely man-made. An inert (non-reactive) gas, it is often used in electrical insulation and fire prevention.

How is climate different than weather?

Climate is long-term. Weather is more current and short term.

What are the causes of medium term climate change?

Earth/sun effects on climate.

What are the three ways that the Earth-sun relationship can change?

Eccentricity cycle - Changes in the Earth's orbit around the sun. Over 100,000 years. Obliquity - Changes in the tilt of the Earth. Over 41,000 years. Wobble - Direction that the poles are pointing. Over 23,000 years.

What are some methods we use to study past climates?

HIstorical and instrumental records (thermometers, rain gauges) to tell what the climate was like. We can use Proxy Data (clues in natural records). Sediments at the bottom of oceans, locked in coral reefs, preserved in rings of trees, frozen in glaciers and ice caps.

What is evidence for climate change?

Historical and instrumental records of temperature Proxy data - clues in natural records such as sediments at the bottom of oceans, locked in coral reefs, preserved in rings of trees, frozen in glaciers and ice caps

How did humans affect climate change?

Humans affect climate change by putting greenhouse gases into the atmosphere creating the enhanced greenhouse affect. Humans effect climate change by putting gases into the atmosphere that haven't been there for a long time by burning fossil fuels. This upsets the carbon cycle. We are releasing more CO2 than we are taking in. We are killing sinks like trees.

How do volcanoes affect climate change?

If there is an explosive eruption, a lot of ash is released into the atmosphere, and it blocks the sun from warming the Earth.

How do the following methods/resources give us information about the past climates? Instruments, tree rings, ocean and lake sediments, ice cores.

Instruments (thermometers, barometers, anemometers) and satellites - They can tell us the exact temperature, pressure or wind speed of something. Satellites can give us a literal picture of the Earth. Tree rings - Precipitation, gas levels (components in wood like the density, the gases present, the thickness, if there is a scorch line from a fire) If there is a larger ring, there was more precipitation that year. If there is a smaller ring, there was less precipitation. Ocean and lake sediments - They give us a record of the sediments. We could see if there was a volcanic explosion from the ash. The sediments collect and settle in layers. We can learn what stuff was living from pollen - trees, plants. Ice cores - Scientists can learn about the gases in the bubbles in the ice. They can learn about the atmosphere. They can learn about the concentrations of gases like CO2 and the historical record of temperatures. They could find preserved organisms. Scientists measure the Co2 levels in the air bubbles to estimate the amount of Co2 during that time period. They can also measure the PH levels. The higher the acid, the lower the Ph. Co2 is acid. More acid, more Co2. Highest acidity = lowest Ph. Sources of the sediments in the ice are volcanoes and pollution.

What are some causes of long-term climate change?

Intensity of the sun and plate tectonics

How do plate tectonics relate to long term climate change?

It has to do with the distribution of land masses. When land masse are spread out, water is able to circulate and regulate temperature. When they aren't spread out, water can't get around land masses and temperatures at the bottom of the continent are super cold. This creates ice. The ice reflects sun away from the Earth, cooling it down more and creating more ice.

What are three different lengths of time for causes of climate change? Over what length of time do these areas cause climate change?

Long term causes - over millions of years Medium term causes - over thousands of years Short term causes - a few to hundreds of years

What is climate?

Long term, large scale trends in weather patterns and conditions.

Is the greenhouse effect always negative? What are some positive aspects?

No, it is not always negative. Some positive aspects are that the greenhouse gases keep heat in. If there was no heat kept in, it would be too cold. Also, the ozone protects us from UV light. Some other positive aspects include the snow melting in the Western Mountains (where we are) there will be an increase in the agricultural yield in some regions. Animals that thrive in warm climates could live longer.

What are the Milankovitch cycles?

The Earth and sun's effects on climate. They are the eccentricity cycle, the obliquity and the wobble.

What is the "Goldilocks Principle?"

The Earth is the perfect distance away from the sun. Not too far and not too close. "Venus is too hot (450 degrees C), Mars is too cold (-53 degrees C), and Earth is just right (13 degrees C)"

What is the greenhouse effect? What is the enhanced greenhouse effect?

The greenhouse effect is the process where light/heat/energy from the sun heats up the ground when it passes through the atmosphere. It also is absorbed by molecules in the atmosphere. The soil gives off infared radiation which gets trapped in the atmosphere. Basically, greenhouse gases trap heat in the atmosphere. The enhanced greenhouse effect is this same process, but created by humans. We have built up tons of gases. We are releasing more greenhouse gases than would ever be created by natural processes.

What is paleoclimatology?

The study of past climates.

How has the climate changed over the history of the earth?

There have been ice ages and warm cycles.

What does it generally mean if we have a large landmass at the North or South pole?

There is likely to be a lot of ice. Water can't circulate and regulate temp, ice forms, ice reflects sunlight away from the Earth which would have warmed Earth up more, so more ice is created. This cycle continues until Earth is almost completely frozen - Snowball Earth. Creates mass extinction.

How do the seasons happen?

Tilt and how the Earth is moving.

What are the causes of short-term climate change?

Volcanic activity - A huge explosions puts ash into the atmosphere which then blocks the sunlight and cools down the Earth.

What are some of the ways we can lessen our impact on global climate change?

We can lessen our impact on global climate change by reducing the amount of Co2 we put in the atmosphere by buying foods locally or driving less/taking public transportation. We could also stop eating so much meat from cows. If we did, we would reduce the amount of methane the cows produce in their digestive systems. We could reduce the amount of sinks (photosynthetic organisms like trees, plants, algae) we destroy Reduce the amount of fossil fuels we burn.

Why do we study paleoclimate?

We study paleoclimate to learn about the climate before humans started collecting instrumental measurements of weather. This includes the collection of past climate conditions and investigates the climate processes underlying these conditions. These studies help us understand about the temperature rise we are experiencing currently.

Why do we study past climates?

We study past climates to learn about how much the climate has changed in the past and the patters that have occurred. We can then apply this knowledge to our current increase in temps. We can use the knowledge that climate can change very quickly so that we are not surprised by a sudden spike or drop in temps.