This blog post was written by Diego Jimenez

“Come gather round people
Wherever you roam
And admit that the waters
Around you have grown…”

from ‘The Times They Are a-Changin,’ Bob Dylan (1964)


When Dylan wrote the 1964 classic about change, climate change was likely the last thing on his mind; yet the lyrics ring hauntingly true today. Climate change is the defining threat to our planet and its community of life, a community that we all belong to. Humans, plants, and animals everywhere, from deserts to oceans to cities and farms, are already suffering the consequences of climate change. Climate change is a major threat because it has the potential to leave no corner of the world untouched. Indeed, because climate change is a global issue, all species are likely to be affected, even those not already threatened by human activities. As if that wasn’t enough, the pace at which climate change is happening leaves species no time to adapt to their changing environment.

It may be difficult to imagine that our oceans, covering nearly three quarters of the planet, could be so vulnerable to climate change. Yet this is exactly the case! As we persist on using fossil fuels for the majority of our energy and transportation, we are continually pumping an ever-increasing amount of greenhouse gases like carbon dioxide (CO2) into the atmosphere. This higher concentration of greenhouse gases in the atmosphere and the unprecedented rate at which it is accumulating are causing a relatively rapid rise in overall global temperature. The results are proving devastating and our oceans are a clear example.

The rising temperatures trigger the melting of glaciers and ice sheets. The melting ice eventually flows into the ocean, leading to sea level rise. As the seas rise coastlines recede, posing a serious threat to the livelihood of people and plant and animal species that live on and depend on those coastlines. The oceans also act as natural carbon sinks. As the surface of ocean water comes into contact with air, it absorbs greenhouse gases such as carbon dioxide from the atmosphere, which is a natural process. However, the excess of CO2 in the ocean is causing serious and unprecedented changes, such as changing its chemical composition and causing shifts in long-established currents. This is bad news for marine species and bad news for us.

One way to understand the effect of climate change on the oceans is to review how it affects species. As an example, we can examine coral and sea turtles, species we are all familiar with.

Coral: A Shaky Foundation

Stony corals - Photo courtesy of NOAA

Stony corals – Photo courtesy of NOAA

Covering just 1% of the ocean floor but supporting approximately a quarter of all known marine life, coral reefs are literally the bedrock of vital marine ecosystems. But coral reefs are highly dependent on a stable temperature in their environment for their survival. As water temperatures rise due to human-caused climate change, coral expel the symbiotic algae that provides them with essential nutrients and their stunning array of colors and end up turning a ghostly shade of white, or what is known as bleaching. While bleaching events do not actually kill the coral, they leave it under additional stress and significantly weakened, which will likely lead to death. Climate change is leading to increasingly warmer oceans thereby making coral bleaching events more common and more frequent; like a domino effect, this could set off a chain of irreparable ecosystem collapse. The loss of coral would not only be catastrophic for marine ecosystems, it would also be devastating for humans given that coral reefs support the livelihoods of an estimated half a billion people.

Sea Turtles: A Battle for Survival


Sea turtles, which also depend heavily on coral reefs for shelter and food, are another sobering example of a marine species affected by climate change. Sea turtles have been around for an estimated 110 million years, having survived the mass extinction that eradicated the dinosaurs. However, all seven species of sea turtles are now listed as vulnerable or endangered with extinction by the IUCN Red List of Threatened Species. Threats to sea turtles include poaching, ocean pollution, loss of nesting beaches, oil spills, and entanglement in fishing nets. But as you might have guessed, climate change could aggravate all of these threats. Sea turtles are ectotherms, or animals that depend on external sources of heat to regulate their temperature, which means they are also highly sensitive to changes in their environment. In fact, the gender of sea turtle hatchlings depends on the surrounding temperature. A warmer world could lead to increased female bias in hatchlings, since higher temperatures yield more female sea turtles than males. If the ratio of females to males grows increasingly out of balance, it could spell serious trouble for the successful reproduction of these ancient marine reptiles. As mentioned before, a warmer world could also lead to the loss of nesting beaches due to rising sea levels, and make it more difficult for sea turtles to find food due to changes in long-established ocean currents and migration patterns. As a result, sea turtles are exceedingly susceptible to the threat of climate change.

There is no time to waste. We need everyone to pitch in for the protection of coral, sea turtles, and marine species overall. Human-caused climate change has the potential to throw our oceans into chaos.

So what can you do?

Take Action!


While the threat of climate change sounds dire, and it is, the good news is that we can all take immediate actions to minimize our impact. Here are a few suggestions:

  • Become an informed citizen by reading about climate change and its effects from independent or peer-reviewed sources
  • Drive less by taking public transportation, biking or walking, or carpool with others as often as you can
  • Seek out renewable energy sources that may service your community and take energy efficient measures at home, such as using energy efficient appliances
  • Choose local, organic or “in season” food and minimize your consumption of meat as much as possible, which may also benefit your health
  • Support conservation organizations such as Turtle Island Restoration Network, which are dedicated to the protection and conservation of our oceans and their wildlife
  • Make your voice heard by voting and making eco-conscious purchases, and also educate those around you about climate change and other environmental issues
  • Lastly, you can check out these additional resources for more information:

We must all contribute to the protection and conservation of the species with which we share this planet. It is our moral obligation and we owe it to the future generations who will inherit this Earth. The time to act is now. We must all gather ‘round and take action, for the tides they are a-changin’…

Diego Jimenez lives and works in Chicago. He is currently a graduate student in the Advanced Inquiry Program through Miami University and the Chicago Zoological Society . He also volunteers as a Penguin Encounters facilitator at Shedd Aquarium and is a certified SCUBA diver. His focus is community-based conservation of coastal regions.