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released, greenhouse gases are trapped in atmosphere, temperature heats up even more, more permafrost melts and more greenhouse gases are released. And slowly, but surely, the planet starts to heat up.
Why is this an issue?
Well, as the permafrost melts, several issues begin to occur. Where the permafrost previously lay underneath steady, hard land due to it providing a solid base, and as it melts things such as erosion, disappearance of lakes, landslides and habitats being destroyed occur. And then there are also the added problems caused by climate change such as sea levels rising, increased risks of droughts, flooding, extreme weather and forest fires along with rising temperatures. And all of this occurs because of the release of greenhouse gases.
This is because greenhouse gases trap heat, so when we emit it from our cars and things such as fossil fuel burning plants and it gets trapped by the atmosphere, once too much gets up there, Earth can begin to heat up. More specifically this is because GHGs are nearly transparent to solar radiation, so the radiation from the sun can enter easily, but it is practically opaque to to thermal radiation that is emitted back by the Earth. This means that the the sun’ s radiation can enter and heat the Earth, and in turn the Earth emits a portion of the energy back into space in the form of longer wavelengths than what the solar radiation was. The GHGs then absorbs and reradiates the heat molecules back down to Earth so we have additional heat energy. So then, the Earth begins to heat up. And because of this heating and the problems that it causes, such as extreme weather, droughts and floods, our organisms in New Zealand begin to become affected
What is the science behind the increase of droughts, flooding and extreme weather?
Flooding and Droughts: Why flooding is increased by global warming relies on firstly, on what feeds rain. This being water vapour, but to find the actual reason we have to first look into where the water vapour comes from. Around 60 % of the water vapour comes straight from our oceans as it evaporates off the surface. The other 40 % is known as being“ recycled” over continents. As an example, you need only to look at China: China, gets most of its rain from evaporation over Eurasia.