According to a study conducted by NASA, atmospheric carbon dioxide is at an all-time high with a constant upward slope since the industrial revolution. Of the effects of carbon dioxide, Dr Phil Bierwirth of the Australian National University has this to say, "although humans and animals are able to deal with elevated levels of CO2 in the short-term due to various compensation mechanisms in the body, the persistent effects of these mechanisms may have severe consequences in a perpetual environment of elevated CO2." An extremely high level of carbon dioxide in the air will eventually result not only in human diseases but furthermore deterioration of the biophysical environment. 

Sustainability and saving the seas have never been more popular advocacies in the recent years. With increasing carbon dioxide levels in the atmosphere, the ocean's pH levels continue to decrease, making waters more acidic. This acidity results in the changing temperatures and hostile conditions for ocean life. Coral reefs are also affected greatly, resulting in a phenomenon called, "bleaching". Bleached corals are basically decaying or dead corals, rendering them inhabitable. According to the US National Ocean Service, "In 2005, the U.S. lost half of its coral reefs in the Caribbean in one year due to a massive bleaching event."

Additionally, in a 2018 National Graphic issue, they discuss how 'half of the Great Barrier Reef is now dead'. The article mentions, "[It] has been bleached to death since 2016. Mass coral bleaching, a global problem triggered by climate change, occurs when unnaturally hot ocean water destroys a reef’s colourful algae, leaving the coral to starve. The Great Barrier Reef illustrates how extensive the damage can be: Thirty percent of the coral perished in 2016, another 20 percent in 2017. The effect is akin to a forest after a devastating fire. Much of the marine ecosystem along the reef’s north coast has become barren and skeletal with little hope of recovery."

Ice sheets are important in balancing the water levels across the entire globe. With warmer waters, there have been significant "glacial melts in Antarctica and Greenland... [this] also influences ocean currents, as massive amounts of very cold glacial-melt water entering warmer ocean waters is slowing ocean currents. And as ice on land melts, sea levels will continue to rise", says the World Wildlife Fund.

In an article by the Climate Change Guide they discuss the areas to be affected by melting ice sheets, "some of the world's largest cities such as Lagos and Shanghai could be significantly affected by rising sea levels. Also, island countries such as Maldives would be one of the first nations to be swallowed up whole along with parts of the United States, mainly around the gulf coast region. Additionally, any city or region in the world that is below sea level will see a drastic rise in floods." 

There has been a strong debate whether climate change can really create extreme global effects or whether it can be the principal cause for such phenomena. In an in-depth study entitled, Changes in Climate Extremes and their Impacts on the Natural Physical Environment, coordinating lead authors Sonia Seneviratne and Neville Nicholls along with other contributors mention that there is not a singular cause to extreme natural disasters. Here, they carefully analyse data from several sources. They survey occasions of drought, floods, extreme sea levels, waves, coastal impacts, sand and dust storms, and glacial retreats.

They note, "...it is challenging to associate a single extreme event with a specific cause such as increasing greenhouse gases because a wide range of extreme events could occur even in an unchanging climate, and because extreme events are usually caused by a combination of factors. Despite this, it may be possible to make an attribution statement about a specific weather event by attributing the changed probability of its occurrence to a particular cause. For example, it has been estimated that human influences have more than doubled the probability of a very hot European summer like that of 2003."

All in all, climate change cannot be denied any longer. An immense catalogue of literature is present that not only supports the thesis that it exists but also reviews its actual effect around the globe. The factors mentioned above work hand-in-hand to create a cascading effect that cuts across biospheres, countries, and territories. Still, the fight is not over and there are a lot of advocates that champion this cause. 

For more references on climate change and its effects, read more here:
Evidence of Climate Change by NASA
U.S. Coastal Flooding Breaks Records as Sea Level Rises
Hurricanes, Typhoons and Cyclones
Climate Science Special Report
The Intergovernmental Panel on Climate Change
United Nations Climate Action Summit 

See also: Truths And Myths Of Sustainability