Hi Alex here. Is climate change really human-made? There's been a lot of research and reports published over the years and I don't blame you if you don't want to read it all so here is what we know for sure in 3 minutes. Let's get drawing! It all started in 1998 when an ice-drilling project was undertaken in the Russian Vostok Station in Antarctica. The project yielded the deepest ice-core ever recovered giving access to ice that was 420,000 years old at a depth of 3,623 meters. It supplied data about atmospheric composition and climate through 4 climate cycles. So here is how it all works: the formation of the glaciers results from the transformation of water into ice during this process which can last thousands of years sediments air and rocks are stuck into the ice making millions of layers one above the other in chronological order. Over the time, the glacier becomes a million page history book with the last chapter on the top.
The deeper you drill the older the compounds are. The ice core gave access to climate data including local temperature, precipitation rate, wind strength, etc. but also and this is what we are interested in here the ice core provided direct records of past changes in atmospheric trace-gas composition thanks to their entrapped air inclusions. Then it was possible to determine the levels of carbon dioxide (CO2) and methane (CH4) at a given time so here is what global temperature and atmospheric concentrations of carbon dioxide and methane look like over for climate cycles 420,000 years So you can clearly see the four climate cycles and you also see that they have very similar spikes and patterns there is clearly a relationship between temperature carbon dioxide and methane. The upper and lower boundaries up the three variables are tightly constrained which is typical a self-regulating system. Our body is also a self-regulating system and does something similar in a way: when you exercise your body sweats as a way to regulate its temperature well on Earth when concentrations of carbon dioxide and methane go up global temperature goes up too.
Now here is what happened with the concentration of atmospheric CO2 since 1960: it increased by about 70 parts per million that is more than one part per million each year indicating significant human perturbation in the self-regulating of Earth since the beginning of the Industrial Revolution As this concentration is now way over the upper boundary noted during the last 420,000 years and as the Earth seems to be a self-regulating system well we can expect the global temperature to increase as well and we are already seeing this worlwide. Since the Vostok research was published more recent ice cores were performed by the European Project for Ice Coring in Antractica (the EPICA) they provided data for the last 800,000 years and confirmed the findings in Vostok so as the Intergovernmental Panel on Climate Change simply puts it in their 2013 report: "human influence on the climate system is clear" and we can safely say that we human beings are responsible for climate change So please subscribe to learn more about sustainability through short animation videos and thank you for watching.