Maths homework Wk 5 (due June 1st)

Sheet ONE

Sheet TWO

Acid Rain - useful sites

These sites all seem really useful. Most have good diagrams, and link you through to more resources.

Fact sheet- acid rain

US Environment Protection Agency - lots of good follow through questions/answers

National Geographic

Conserve Energy Future

Britannica

Really good youtube clip

Water Worries - activities

Define these words:

• Vapour
• Irrigation
• Aquifers
• Sewerage
• Desalination

Answer the following question is full sentences. Be sure to involve the question in your response.

1. What does the author mean when she says our problems have “only just started”? (pg 38)
2. What is the 'big idea' of this text?
3. How much difference do you think individuals can make?

List 7 consequences of pollution entering water systems.

Research questions
What are the 5 longest rivers in the world?
What is New Zealand’s longest river? How long is it?

Maths links for wk 3 - 14/5 to 18/5

Strand work  - AWS, rounding and estimating

BEDMAS practice - AWS tasks 6 & 7

Homework sheets - incase you leave them at school!  Sheet 1,  Sheet 2&3

Water Cycle links to help you

This link has a simple description of each stage, and a good diagram.

This link for a pretty good description. Really starts half way down the page.

This link for a very short and concise explanation.

Current Events sheet

Hello literacy class :)

Here is the link to the current events sheet. You can now print it at home if you have forgotten the sheet at school.

Remember, this is DUE EACH FRIDAY.

Below is the list of what you are doing, and which week you are presenting. Remember, even f not presenting, you still do the sheet each week!

Kanika	Local	wk 2
Olivia	Local	wk 2
Matthew C	Local	wk 3
Ethan	Local	wk 3
Skylar	Local	wk 4
Jacob	Local	wk 4
Matthew V	Local	wk 5
Elizabeth	Local	wk 5
Grace B	National	wk 2
Zander	National	wk 2
Adi	National	wk 3
Preston	National	wk 3
Ruby	National	wk 4
Maryann	National	wk 4
Mardi	National	wk 5
Siobhan	International	wk 2
John-Luke	International	wk 2
Grace G	International	wk 3
Kion	International	wk 3
Micah	International	wk 4
Luke	International	wk 4
Madeleine	International	wk 5

Maths AWS tasks

Maths AWS tasks

The Carbon Cycle

The Carbon Cycle

Learn how carbon moves through Earth's ecosystems and how human activities are altering the carbon cycle.

 

Key points

·      Carbon is an essential element in the bodies of living organisms. It is also economically important to modern humans, in the form of fossil fuels.

·      Carbon dioxide from the atmosphere is taken up by photosynthetic organisms and used to make organic molecules, which travel through food chains. In the end, the carbon atoms are released in respiration.

·      Slow geological processes, including the formation of sedimentary rock and fossil fuels, contribute to the carbon cycle over long timescales.

·      Some human activities, such as burning of fossil fuels and deforestation, increase atmospheric CO₂ and affect Earth's climate and oceans.

Carbon: building block and fuel source

About 18% of your body consists of carbon atoms, by mass, and those carbon atoms are pretty key to your existence!  Without carbon, you wouldn't have the plasma membranes of your cells, the sugar molecules you use for fuel, or even the DNA that carries instructions to build and run your body.

Carbon is part of our bodies, but it's also part of our modern-day industries. Carbon compounds from long-ago plants and algae make up the fossil fuels, such as coal and natural gas, that we use today as energy sources. When these fossil fuels are burned, carbon dioxide, CO₂, is released into the air, leading to higher and higher levels of atmospheric CO₂. This increase in CO₂ affects Earth's climate and is a major environmental concern worldwide.

Let's take a look at the carbon cycle and see how atmospheric CO₂ and carbon use by living organisms fit into the bigger picture of carbon cycling.

The Carbon Cycle

The carbon cycle is most easily studied as two interconnected sub-cycles:

·      One dealing with rapid carbon exchange among living organisms

·      One dealing with long-term cycling of carbon through geologic processes

Although this explanation will look at them separately, it's important to realize these cycles are linked. For instance, the same pools of atmospheric and CO₂ that are utilized by organisms are also fed and depleted by geological processes.

As a brief overview, carbon exists in the air largely as carbon dioxide CO₂ gas, which dissolves in water and reacts with water molecules to produce bicarbonate.   Photosynthesis by land plants, bacteria, and algae converts carbon dioxide or bicarbonate into organic molecules. Organic molecules made by photosynthesizers are passed through food chains, and cellular respiration converts the organic carbon back into carbon dioxide gas.

Long term storage of organic carbon occurs when matter from living organisms is buried deep underground or sinks to the bottom of the ocean and forms sedimentary rock.

Volcanic activity and, more recently, human burning of fossil fuels bring this stored carbon back into the carbon cycle. Although the formation of fossil fuels happens on a slow, geologic timescale, human release of the carbon they contain—as CO₂, is on a very fast timescale.

How does carbon cycle back to the atmosphere or ocean?

To release the energy stored in carbon-containing molecules, such as sugars, autotrophs and heterotrophs break these molecules down in a process called cellular respiration. In this process, the carbons of the molecule are released as carbon dioxide. Decomposers also release organic compounds and carbon dioxide when they break down dead organisms and waste products.

Carbon can cycle quickly through this biological pathway, especially in aquatic ecosystems. Overall, an estimated 1,000 to 100,000 million metric tons of carbon move through the biological pathway each year. For context, a metric ton is about the weight of an elephant or a small car!

The geological carbon cycle

The geological pathway of the carbon cycle takes much longer than the biological pathway described above. In fact, it usually takes millions of years for carbon to cycle through the geological pathway. Carbon may be stored for long periods of time in the atmosphere, bodies of liquid water—mostly oceans— ocean sediment, soil, rocks, fossil fuels, and Earth’s interior.

The level of carbon dioxide in the atmosphere is influenced by the reservoir of carbon in the oceans and vice versa. Carbon dioxide from the atmosphere dissolves in water and reacts with water.

When an organism dies, their remains may sink and eventually become part of the sediment on the ocean floor. Over geologic time, the sediment turns into limestone, which is the largest carbon reservoir on Earth.

On land, carbon is stored in soil as organic carbon from the decomposition of living organisms or as inorganic carbon from weathering of terrestrial rock and minerals. Deeper under the ground are fossil fuels such as oil, coal, and natural gas, which are the remains of plants decomposed under anaerobic—oxygen-free—conditions. Fossil fuels take millions of years to form. When humans burn them, carbon is released into the atmosphere as carbon dioxide.

Another way for carbon to enter the atmosphere is by the eruption of volcanoes. Carbon-containing sediments in the ocean floor are taken deep within the Earth in a process called subduction, in which one tectonic plate moves under another. This process forms carbon dioxide, which can be released into the atmosphere by volcanic eruptions or hydrothermal vents.

Human impacts on the carbon cycle

Global demand for Earth’s limited fossil fuel reserves has risen since the beginning of the Industrial Revolution. Fossil fuels are considered a nonrenewable resource because they are being used up much faster than they can be produced by geological processes.

When fossil fuels are burned, carbon dioxide is released into the air. Increasing use of fossil fuels has led to elevated levels of atmospheric CO₂. Deforestation—the cutting-down of forests—is also a major contributor to increasing CO₂ levels. Trees and other parts of a forest ecosystem sequester carbon, so with less trees, more CO₂ is in the atmosphere.

Why does it matter that there is lots of CO₂ in the atmosphere? 

CO₂ is a greenhouse gas. When in the atmosphere, it traps heat and keeps it from radiating into space. Based on extensive evidence, scientists think that elevated levels of CO₂ and other greenhouse gases are causing pronounced changes in Earth's climate. Without decisive changes to reduce emissions, Earth's temperature is projected to increase by 1 to 5ºc by the year 2100.

Activities to go with this explanation

The Carbon Cycle - activities

Define these words;

·      organism

·      sedimentary rock

·      altering

·      depleted

·      decisive

·      autotrophs

·      heterotrophs

Give full sentence answers.

1.     How is carbon economically important to people?

2.     How does the long term storage of carbon occur in nature?

3.     Explain how fossil fuels are a non-renewable resource.

4.     How is the carbon cycle similar to the water cycle?

5.     How is deforestation adding to the problem of climate change?

Try to draw a model using either words, simple pictures, or both, that shows the carbon cycle.