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2 What needs to be done? On this page:What is Global Warming and Climate Change? What are the main indicators of Climate Change? What do we have to do with it? The climate has always varied in the past.
Doesn’t recent record cold weather disprove Global Warming? Has global warming paused due to recent surface temperature drops? What are the impacts of Global Warming? What is Global Warming and Climate Change? Global warming and climate change refer to an increase in average global temperatures. Natural events and human activities are believed to be contributing to an increase in average global temperatures. A warming planet thus leads to a change in climate which can affect weather in various ways, as discussed further below.
The greenhouse effect is the rise in temperature on Earth as certain gases in the atmosphere trap energy. Many of these greenhouse gases are actually life-enabling, for without them, heat would escape back into space and the Earth’s average temperature would be a lot colder. However, if the greenhouse effect becomes stronger, then more heat gets trapped than needed, and the Earth might become less habitable for humans, plants and animals. Carbon dioxide, though not the most potent of greenhouse gases, is the most significant one. Human activity has caused an imbalance in the natural cycle of the greenhouse effect and related processes. When we mine coal and extract oil from the Earth’s crust, and then burn these fossil fuels for transportation, heating, cooking, electricity, and manufacturing, we are effectively moving carbon more rapidly into the atmosphere than is being removed naturally through the sedimentation of carbon, ultimately causing atmospheric carbon dioxide concentrations to increase.
The result is that humans are adding ever-increasing amounts of extra carbon dioxide into the atmosphere. Because of this, atmospheric carbon dioxide concentrations are higher today than they have been over the last half-million years or longer. Too much salt can be harmful to our health. The other difference between the natural carbon cycle and human-induced climate change is that the latter is rapid. This means that ecosystems have less chance of adapting to the changes that will result and so the effects felt will be worse and more dramatic it things continue along the current trajectory. Throughout Earth’s history the climate has varied, sometimes considerably. Past warming does not automatically mean that today’s warming is therefore also natural.
Recent warming has been shown to be due to human industrialization processes. Less heat escaping to space, shrinking thermosphere, cooling stratosphere, rising tropopause, less oxygen in the air, more fossil fuel carbon in the air, 30 billion tonnes of C02 per year, more heat returning to Earth, nights warming faster than days, and more fossil fuel carbon in coral are all signs of human-induced climate change. Climate Change: How do we know? 2013, last accessed February 1, 2015.