This document discusses climate change and carbon dioxide emissions. It begins with an introduction to climate change, then discusses carbon dioxide levels and various natural and human sources of carbon dioxide emissions. It also covers carbon sequestration, the importance of reducing energy consumption, the need for de-carbonization, deforestation causes and drivers, and provides a bibliography.

1. #SCICHALLENGE2017
Students: Cherim Haluk
Damian Robert-Costin
Goldic Vlad-Stefan
“Ovidius’’ High School of Constanta,Romania
Teacher: Bucovala Carmen

2. Climate change

3. INTRODUCTION
Climate change is a change in the statistical distribution of weather patterns
when that change lasts for an extended period of time (i.e., decades to millions
of years). Climate change may refer to a change in average weather conditions,
or in the time variation of weather around longer-term average conditions (i.e.,
more or fewer extreme weather events). Climate change is caused by factors
such as biotic processes, variations in solar radiation received by Earth, plate
tectonics, and volcanic eruptions. Certain human activities have been identified
as primary causes of ongoing climate change, often referred to as global
warming.

4. Carbone dioxide
The amount of carbon dioxide in the atmosphere needs to be lowered
and the issue must be addressed from many different angles. Reduction of
releases is the most important issue, but there are also alternative ideas to achive
this goal. There are both natural and human sources of carbon dioxide emissions.
Natural sources include decomposition, ocean release and respiration. Human
sources come from activities like cement production, deforestation as well as the
burning of fossil fuels like coal, oil and natural gas.Due to human activities, the
atmospheric concentration of carbon dioxide has been rising extensively since
the Industrial Revolution and has now reached dangerous levels not seen in the
last 3 million years.1 2 3 Human sources of carbon dioxide emissions are much
smaller than natural emissions but they have upset the natural balance that
existed for many thousands of years before the influence of humans.

5. Carbon Dioxide Emissions:
Natural Sources
Apart from being created by human activities, carbon dioxide is also released into the
atmosphere by natural processes. The Earth's oceans, soil, plants, animals and volcanoes are
all natural sources of carbon dioxide emissions.Human sources of carbon dioxide are much
smaller than natural emissions but they upset the balance in the carbon cycle that existed
before the Industrial Revolution. The amount of carbon dioxide produced by natural sources
is completely offset by natural carbon sinks and has been for thousands of years. Before the
influence of humans, carbon dioxide levels were quite steady because of this natural
balance. 42.84 percent of all naturally produced carbon dioxide emissions come from ocean-
atmosphere exchange. Other important natural sources include plant and animal respiration
(28.56%) as well as soil respiration and decomposition (28.56%). A minor amount is also
created by volcanic eruptions (0.03%).

6. Carbon Dioxide Emissions:
Human Sources
Since the Industrial Revolution, human sources of carbon dioxide emissions
have been growing. Human activities such as the burning of oil, coal and gas, as
well as deforestation are the primary cause of the increased carbon dioxide
concentrations in the atmosphere.87 percent of all human-produced carbon
dioxide emissions come from the burning of fossil fuels like coal, natural gas and
oil. The remainder results from the clearing of forests and other land use changes
(9%), as well as some industrial processes such as cement manufacturing (4%).

7. Carbon sequestration
Carbon sequestration is the process involved in carbon
capture and the long-term storage of atmospheric carbon
dioxide. Carbon sequestration involves long-term storage of
carbon dioxide or other forms of carbon to mitigate or defer
global warming. It has been proposed as a way to slow the
atmospheric and marine accumulation of greenhouse gases,
which are released by burning fossil fuels.

8. Consumption
Is reducing energy consumption important for climate change?
It is natural to think that reducing our energy consumption is good for the
climate. We can ride a bicycle instead of driving a car. And if we drive a car, we
can drive a smaller, more fuel-efficient car. These things certainly help reduce
urban noise, congestion, and air pollution. But do they really help to solve climate
change?

9. De-carbonization is key
There are many ways to reduce our energy demand through lifestyle choices
and improved efficiency, with broad environmental and social benefits. But we
should not fool ourselves into thinking that by doing these things, and these
things alone, we necessarily help to solve climate change. We can only solve
climate change by replacing fossil fuels with other sources of energy.
The good news is that these other energy sources exist, and are already
beginning to compete with fossil fuels on an even footing. Our energy
consumption choices can help to accelerate their adoption. Every switch from oil
to electricity, whether in mobility or home heating, matters. Some of those
choices may involve using less energy, but others may involve using more. To
stop climate change it is far more important where our energy comes from than
simply how much of it we use.

10. Deforestation
Deforestation, clearance or clearing is the removal of a forest or stand of trees
where the land is thereafter converted to a non-forest use.Examples of
deforestation include conversion of forestland to farms, ranches, or urban use.
The most concentrated deforestation occurs in tropical rainforests. About 30% of
Earth's land surface is covered by forests.
The removal of trees without sufficient reforestation has resulted in damage to
habitat, biodiversity loss and aridity. It has adverse impacts on biosequestration of
atmospheric carbon dioxide.

11. Causes for deforestation
The degradation of forest ecosystems has also been traced to economic
incentives that make forest conversion appear more profitable than forest
conservation.Many important forest functions have no markets, and hence, no
economic value that is readily apparent to the forests' owners or the communities
that rely on forests for their well-being.From the perspective of the developing
world, the benefits of forest as carbon sinks or biodiversity reserves go primarily
to richer developed nations and there is insufficient compensation for these
services. Developing countries feel that some countries in the developed world,
such as the United States of America, cut down their forests centuries ago and
benefited economically from this deforestation, and that it is hypocritical to deny
developing countries the same opportunities, i.e. that the poor shouldn't have to
bear the cost of preservation when the rich created the problem.

12. Some commentators have noted a shift in the drivers of deforestation over the past 30
years.Whereas deforestation was primarily driven by subsistence activities and
government-sponsored development projects like transmigration in countries like
Indonesia and colonization in Latin America, India, Java, and so on, during the late 19th
century and the earlier half of the 20th century, by the 1990s the majority of
deforestation was caused by industrial factors, including extractive industries, large-
cale cattle ranching, and extensive agriculture.
Experts do not agree on whether industrial logging is an important contributor to
global deforestation. Some argue that poor people are more likely to clear forest because
they have no alternatives, others that the poor lack the ability to pay for the materials
and labour needed to clear forest. One study found that population increases due to high
fertility rates were a primary driver of tropical deforestation in only 8% of cases.

13. Bibliography
http://whatsyourimpact.org
https://en.wikipedia.org
https://www.ethz.ch

14. Thank you for watching!