Coral Reefs are Dying Because of Climate Change.

  Pro: Coral Reefs are Dying From The National Oceanic and Atmospheric Administration: Climate change is the greatest global threat to coral reef ecosystems. Scientific evidence now clearly indicates that the Earth’s atmosphere and ocean are warming, and that these changes are primarily due to greenhouse gases derived from human activities. As temperatures rise, mass coral bleaching events … are becoming more frequent.  

Additionally, carbon dioxide absorbed into the ocean from the atmosphere has already begun to reduce calcification rates in reef-building and reef-associated organisms by altering seawater chemistry through decreases in pH. This process is called ocean acidification. 

 Climate change will affect coral reef ecosystems, through sea level rise, changes to the frequency and intensity of tropical storms, and altered ocean circulation patterns. When combined, all of these impacts dramatically … [harm coral reef] ecosystems … around the globe.

 Con: Coral Reefs are Thriving Coral reefs are thriving around the globe. Coral has existed continuously for the past 40 million years, surviving temperatures and carbon dioxide levels significantly higher and lower than what is occurring today.

Since the peak of the last glacial maximum 33-26 thousand years ago, global average temperature reached its highest point approximately 7,000 years ago, at least 1 or 2 degrees C higher than today, during which coral reefs thrived.

 

Coral requires warm water, not cold water, to live. Coral cannot live outside of tropical or subtropical waters. Coral reefs thrive in locations throughout the globe where temperatures range from site to site by as much as 20 degrees Fahrenheit, from the most Northern or most Southern sites to the most equatorial sites. The temperature at coral reef sites range by over 20 degrees Fahrenheit from Summer to Winter at some locations around the world. 

Thus, coral reefs have proven to thrive in a substantial range of temperature environments, including temperatures that exceed those where coral bleaching has occurred. 

As Earth continues its modest warming since the peak of the Little Ice Age 400 years ago, coral reefs have extended their range toward the poles while still thriving at and near the equator. 

Temperature Swings: Short-term heatwaves or cold snaps can cause bleaching events, but historically, such events have occurred long before the recent warming since the peak of the Little Ice Age. 

Moreover, studies show coral can and have been adapting to the gradual long-term pace of global warming that has occurred since the peak of the Little Ice Age. History shows that cold snaps can harm coral much worse than warm spells. 

In 2010, colder ocean temperatures off the coast of Florida killed more coral than any warm-water event. And, despite these events, coral reefs recover over the course of several years or sometimes, even quicker.

Courtesy "Everything Climate "