A changing climate is a normal part of the Earth’s dynamic system which warms and cools over timescales of tens of thousands of years. The problem we are experiencing is that we are changing the system at rapid rate and this is mostly due to the anthropogenic release of greenhouse gasses (GHG), such as Carbon Dioxide, through the burning of fossil fuels (Solomon et al., 2009). The existence of greenhouse gasses in the atmosphere such as carbon dioxide, methane and water vapor are completely normal and is in fact crucial for the ability of Earth to sustain life. Because of their chemical makeup they have the ability to absorb heat which is emitted by the sun (solar radiation) (Eriksson, 1978). The problem which we are facing is that humans have been producing more carbon dioxide than is naturally occurring in the atmosphere, and the system cannot keep up with the rapid input of GHG. When the amount of GHGs increases they are able to retain more heat, this is what is causing global warming (Solomon et al., 2009). 

In a natural system there are feedback loops which keep the components of earth such as temperature and sea level in equilibrium; which only change slightly over centuries. In the past when there has been a change in Carbon Dioxide there have been correlating changes in the mean temperature and sea level. Studying the Vostok ice cores, we are able to have an in-depth overview of these changes over the last 400 000 years (Caillon et al., 2001). In these ices cores there are pockets of air which were frozen at the time of the ice formation and from these scientists have been able to confirm the link between increasing Carbon Dioxide and increasing mean Earth temperatures (Caillon et al., 2001).

By confirming with other types of evidence around the world the correlation between rising Carbon Dioxide and rising global temperatures has been confirmed, as well as a link to the rising in sea level. The Carbon Dioxide level is at currently at 409 ppm (NOAA, 2019) and the last time it was this high was 65 000 years ago and the global temperature was much higher than today. This is why scientists believe that we are going to experience a rise in global temperature and these changes are already happening. Over the last 30 years the Carbon Dioxide levels have risen from 351 ppm to 408 ppm and the global temperature has risen by 0.85 °C (IPCC, 2014). These changes in the Carbon dioxide levels and consequential warming are expected to cause serious negative impacts on the Earths system such as sea level rise, coral bleaching events, changes in storm risk and ocean acidification. 

Reference:

Caillon, N., Severinghaus, J., Barnola, J., Chappellaz, J., Jouzel, J. and Parrenin, F. (2001). Estimation of temperature change and of gas age-ice age difference, 108 kyr B.P., at Vostok, Antarctica. Journal of Geophysical Research: Atmospheres, 106(D23), pp.31893-31901.

 Eriksson, E. (1978). The atmospheric carbon dioxide problem. Tellus, 30(4), pp.350-357.IPCC, 2014: Climate Change 2014: Synthesis Report. Contribution of Working Groups I, II and III to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change [Core Writing Team, R.K. Pachauri and L.A. Meyer (eds.)]. IPCC, Geneva, Switzerland, 151 pp. 

NOAA (2019). ESRL Global Monitoring Division – Global Greenhouse Gas Reference Network. [online] Esrl.noaa.gov. Available at: https://www.esrl.noaa.gov/gmd/ccgg/trends/monthly.html [Accessed 14 Sep. 2019].

Solomon, S., Plattner, G., Knutti, R. and Friedlingstein, P. (2009). Irreversible climate change due to carbon dioxide emissions. Proceedings of the National Academy of Sciences, 106(6), pp.1704-1709.