The Threat of Climate Change


The Threat of Climate Change

Recent international reports on climate change depict a bleak future.

Among the findings:

  • Even if nations succeed in meeting the frequently cited goal of keeping warming below 2 degrees Celsius in the coming century, the world’s coral reefs would virtually disappear; as many as 80 million people would be exposed to flooding; more than 400 million people would be exposed to drought; and about 37 percent of the world’s population could suffer extreme heat.
  • Higher than expected amounts of heat have been measured in the ocean, meaning more heat remains within the Earth’s climate system each year.
  • Temperatures were only slightly higher than what they are today when major parts of the Antarctic ice sheet melted 125,000 years ago and sea levels were 20 feet higher than they are today.

Some will dismiss such studies as fear mongering to promote a political agenda. Granted, the scientific consensus is not always correct and all predictions merit a certain amount of skepticism.

Yet the reality is the overwhelming majority of scientists believe, and numerous peer-reviewed studies affirm, that human-made climate change is occurring with destructive consequences, including more volatile weather.

The Florida Aquarium scientists are not involved directly in climate research, but they observe its impacts and worry about the effects on both marine life and people.

Dr. Ari Fustukjian, veterinarian, notes that it’s not just about bigger storms and lost beachfront property. There are other, subtler impacts as well. Changes in sea level can mean lost nesting sites for endangered sea turtles, and in cases where nesting still takes place, a temperature change of just a few degrees in the nest can alter gender ratios of developing turtles.

Changes in water temperature have the potential to influence ocean currents, altering the flow of nutrients and shifting food webs at the level of their basic building blocks – zooplankton and algae – small effects that may not be apparent at a glance, but can have a big impact. For example, climate change is considered a potential factor in changes to the movements of the population of Right Whales in the North Atlantic – one of the most endangered marine mammals in the world. Moving out of historically established “protected” areas has resulted in a dramatic upsurge in ship strike fatalities – one of the major threats to this slow-moving species and its approximately 450 remaining members.

Fustukjian believes it is a mistake to view climate change simply as an environmental issue. It affects food production, water availability, flooding, commerce and public health. (Already tropical diseases are spreading northward.)

Keri O’Neil, the The Florida Aquarium Center for Conservation’s coral nursery manager, said warmer temperatures are weakening Florida’s already imperiled coral reefs.

She stressed that climate change is a secondary threat to reefs already are being rapidly destroyed by disease (More on that in a future blog).

She explained the warmer water causes a “breakdown in the relationship that coral has with the algae” that live with the coral and provides nutrition for it.

“The algae start photosynthesizing faster, producing more byproducts that might be harmful to the coral.”

Under these conditions, the algae eventually leave the coral, and the result is the bleaching common throughout the Florida Keys.

O’Neil added the bleaching does not immediately kill the coral. If the algae return in time, the coral can recover. But otherwise algae-less coral will end up “starving and dying.”

Rising temperatures and ocean acidification are correlated. Ocean acidification makes it difficult for corals to extract from seawater the calcium that it uses to build its stony structure, O’Neil remarked.

The increased acidification can “actually can start eroding the reef.”

The alarming situation underscores the importance of the Aquarium’s and its research partners’ effort to preserve coral genotypes, and reproduce them in the lab.

Like O’Neil, Fustukjian worries about the acidification of the ocean and its impacts on reefs that are the “like rain forests,” supporting hundreds of different species.”

Without coral reefs, the ocean would lose much of its rich biological diversity that sustains marine life and humans alike.

“The ocean has been a very stable environment for a long time, but now it is undergoing changes like a runaway train,” he said.


Story by Joe Guidry, former opinion editor, The Tampa Tribune



With contributions by:

Dr. Ari Fustukjian, Veterinarian, The Florida Aquarium



Keri O'Neil, Senior Coral Scientist, The Florida Aquarium Apollo Beach


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