Earth Week Lessons: Educating Elementary Students on Coral Bleaching
I groan as the screen flickers to black, marking my efforts to create a perfect fin over the past five minutes obsolete. The charger clicks as it enters the device’s port, and I heave a sigh of relief as my drawing–with the last half-hour’s work intact–lights up the screen. I finally complete the sea turtle’s fin, the final touch to my sketch, which is soon to be distributed as a coloring sheet within my school’s Peer Environmental Leadership Earth Week launch. This launch, focused on the climate change-induced phenomenon of coral bleaching and targeted toward elementary students, contains not only my coloring sheet displaying the contrast between bleached and flourishing coral environments but also a children’s story, explanatory video, and several other interactive activities. The explanatory video, designed and executed by two of my peers and me, details the process of coral bleaching in simple, easily digestible terms.
The first Earth Day occurred in April of 1970 as a means of supporting a national agenda to regulate industry and protect the natural world. A major goal of the environmental movement at this period was to shift focus toward education on climate change and sustainable practices–aspects of this goal were reached, as the Environmental Protection Agency (EPA) was established just several months after Earth Day in July 1970. Although taking action against environmental destruction is the primary objective of the current-day movement, raising awareness remains crucial. While acknowledgment of climate change is certainly more ubiquitous than five decades ago at the birth of Earth Day, numerous detrimental effects of global warming remain elusive to the general public. Coral bleaching, the process by which corals appear transparent and reveal their white skeletons, is a prime example of one of climate change's seldom-recognized impacts.
The process of coral bleaching and coral death in the Great Barrier Reef. Source: The Ocean Action Agenda
In coral bleaching, warmer water temperatures–a result of global warming–prompt corals to expel zooxanthellae. Zooxanthellae is a form of microscopic algae living within the tissues of healthy corals; it aids corals by removing waste and producing food through the process of photosynthesis and also provides corals with their signature vibrant colors. When zooxanthellae depart from stressed corals, the corals are reduced to white skeletons and are at increased risk for starvation and disease.
Coral bleaching in and of itself is not a major concern. In fact, it is simply a natural process, and individual coral colonies experienced bleaching to a minor degree each summer prior to human intervention. The danger of bleaching lies in mass bleaching events, which are caused by large-scale marine heatwaves. These events have a widespread impact and are typically associated with high levels of coral mortality; thus, as global warming causes them to become more frequent and severe, the natural recovery processes of reefs are unable to keep up. For instance, two back-to-back mass bleaching events hit the Great Barrier Reef from 2016 to 2017, collectively affecting over two-thirds of the reef’s corals.
Progression of healthy coral to stressed and bleached coral. Source: National Ocean Service
As the magnitude of climate change continues to increase, reefs become increasingly subject to bleaching. Seemingly minor temperature changes still have an extensive effect on corals; a temperature increase of just one degree Celsius for four weeks can trigger bleaching. Likewise, changes in water quality, sun exposure, and extreme low tides can stimulate bleaching events as well. Yet, although the ramifications of coral bleaching are certainly severe, it is counterintuitive to imply that widely known coral reefs such as the Great Barrier Reef, which contains over 3,000 reef colonies, “have died”. This creates a false pretense by implying finality. In actuality, coral bleaching may be reversible, as reefs can recover as coral communities re-grow and new coral larvae settle on the reef. For this to happen, warming rates must be significantly slowed, and ocean conditions must return to relative normalcy.
As climate change is a global issue with universal implications, one may scoff at raising awareness in his or her local community. However, Earth Day and Earth Week, which have been helping the environmental cause for decades, provide the ideal forum to educate our peers on less acknowledged effects of climate change. Returning to the aforementioned Peer Environmental Leadership Launch, my peers and I were able to distribute our materials on coral bleaching to second-grade, third-grade, fourth-grade, and fifth-grade students across the district through the administration, providing both a fun and educational experience to hundreds of kids. After all, those children should get a chance to see the reefs if they wish, and action must be taken to ensure that prospect.
