//(text-style:"italic","sway")[In a very populated city
lived a very small [[headchog]]
called Scruffy Sammy,
Scruffy Sammy went around the [[city]]
living in feilds,
Gardens, Under [[cars]]
and in the forestry around the [[city]].]//As cities become increasingly important to our lives,
they have become a big source of [[greenhouse gas emissions]].
Because their locations are fixed and they are home to so many people,
urban areas are also among the most vulnerable places in the world
to the impacts of [[global warming]] –
such as [[rising seas levels]].In addition to these emissions of [[carbon dioxide]]
and other [[air pollutants]], the vehicle
and related industries (e.g. [[fuels]])
consume large amounts of raw materials,
and produce significant quantities of waste.Climate change is making our winters generally warmer and wetter,
causing hedgehogs to wake up more often
during a season where food is at its lowest.
Without enough sustenance to replace
the energy they use trying to forage during winter,
hedgehogs may starve. [[start ]]How do greenhouse gas emissions contribute to climate change?
A greenhouse gas is any gaseous compound in the atmosphere
that is capable of absorbing infrared radiation,
thereby trapping and holding heat in the atmosphere.
By increasing the heat in the atmosphere,
greenhouse gases are responsible for the greenhouse effect,
which ultimately leads to global warming.
[[start ]]Global warming is the long-term heating
of Earth's climate system observed
since the pre-industrial period (between 1850 and 1900)
due to human activities, primarily fossil fuel burning,
which increases heat-trapping greenhouse gas
levels in Earth's atmosphere. [[start ]]The major physical impacts of a rise in sea level
include erosion of beaches,
inundation of deltas as well as flooding and loss
of many marshes and wetlands.
Increased salinity will likely become a problem
in coastal aquifers and estuarine systems as a
result of saltwater intrusion. [[start ]]Exposure to CO2 can produce a variety of health effects.
These may include headaches, dizziness, restlessness,
a tingling or pins or needles feeling, difficulty breathing,
sweating, tiredness, increased heart rate,
elevated blood pressure, coma, asphyxia,
and convulsions. [[start ]]Air pollution can also cause headaches,
dizziness, and nausea. ...
Long-term health effects from air pollution
include heart disease, lung cancer,
and respiratory diseases
such as emphysema. Air pollution can also
cause long-term damage to people's nerves,
brain, kidneys, liver, and other organs. [[start ]]When fossil fuels are burned,
they release large amounts of carbon dioxide,
a greenhouse gas, into the air.
Greenhouse gases trap heat in our atmosphere,
causing global warming.
Already the average global temperature
has increased by 1C [[start ]]