In recent years there seems to be somewhat of a kerfuffle over the use of the terms Global Warming and Climate Change. Some in denial about the scientific concerns for changes in our planetary environment have suggested that “they” have changed the terminology to confuse the public. Or denialists claim that the term climate change is employed to cover up for the fact that the planet is not actually warming. Nothing could be further from the truth.
Both terms have been around and in use for years by scientists and mean different things. Realistically climate change is a result of global warming and includes many derived effects in addition to warming. The best way to look at is yet more terminology. Anthropogenically (man-made) driven changes to our planet include overall warming, which directly drives things such as warmer land and sea temperatures, the melting of the polar ice sheets and the recession of glaciers. All of the above has been going on and accurately measured for a couple of centuries. The rate of change is not always constant but the trend is undeniable.
The warming is due to something called radiative forcing. Certain gases produced through human activities, mainly burning fossil fuels, absorb infrared energy (heat ) in the atmosphere. The heat is trapped in the atmosphere rather than radiated out to space. Essentially planetary heat gain and heat loss are out of balance. Carbon Dioxide not only drives the heat cycle but also negatively impacts the oceans.
The oceans are getting warmer due to the direct heating effect, and as there is more water from melting ice, the salinity or saltiness of the oceans is decreasing. Coral bleaching is being observed around the world. Bleaching is the term given to the die-off of coral due to heat and acidity. All that is left is the lifeless exoskeletons which appear white without the living matter present. Coral makes up the reefs that constitute the nurseries of the much of the ocean fish populations.
Wetlands on the continental shelves are being drown from rising sea levels. Wetlands also constitute nurseries for fin fish and shellfish stocks which are threatened. As the water levels rise the brackish water moves farther inland. Jellyfish, which have little nutritional value and therefore aren’t part of a food chain seem to be replacing other valuable organisms around the globe.
The world’s oceans are actually acting to moderate the rate of global warming by absorbing some the Carbon Dioxide from the atmosphere, but this comes at a cost. As the Carbon Dioxide from the atmosphere dissolves in the oceans, it reacts chemically to become more acidic. The same effect is achieved in bottled soda drinks. Carbon Dioxide is the stuff that makes a soft drink fizzy, and also more tart, due to the acidity. The acidity of oceans is directly proportional to the amount of Carbon dioxide absorbed. The worst case scenario is that Calcium Carbonate, the stuff of shells and the bones of animals won’t form.
All these changes are being accelerated by what are known as positive feed back loops. As sea ice melts the surface of the earth becomes less reflective. Less reflectivity means more heat absorption, which leads to more sea ice melting. The longer we delay action the more difficult our predicament becomes.