IELTS Academic Reading Passage – Part III

Passage: The Impact of Climate Change on Coral Reefs

Coral reefs are one of the most diverse ecosystems on the planet, often referred to as the “rainforests of the sea.” They provide essential services, such as supporting marine biodiversity, protecting coastlines from erosion, and contributing to local economies through tourism and fishing. However, coral reefs are increasingly threatened by climate change, which poses a significant risk to their survival.

One of the primary impacts of climate change on coral reefs is ocean warming. As global temperatures rise, the waters surrounding coral reefs also become warmer. Elevated temperatures can cause coral bleaching, a phenomenon where corals expel the symbiotic algae (zooxanthellae) that live within their tissues. These algae provide corals with food through photosynthesis and are responsible for their vibrant colors. When corals experience stress due to higher temperatures, they lose these algae, leading to a loss of color and essential nutrients. If the temperature returns to normal levels, corals can recover, but prolonged bleaching can result in coral death.

In addition to warming waters, ocean acidification—another consequence of climate change—poses a severe threat to coral reefs. The absorption of increased atmospheric carbon dioxide by the oceans lowers the pH levels, making the water more acidic. Acidic conditions hinder the ability of corals to calcify, which is the process of building their calcium carbonate skeletons. This weakening of coral structures makes them more susceptible to erosion and decreases their ability to provide habitat for marine life.

Moreover, climate change can lead to more frequent and severe weather events, such as hurricanes and tropical storms. These storms can physically damage coral reefs, uprooting coral colonies and altering the habitats that many marine species rely on for survival. The combined effects of warming waters, ocean acidification, and increased storm activity create a precarious situation for coral reefs globally.

In conclusion, the health of coral reefs is intricately linked to the stability of our climate. Addressing climate change is vital to preserving these critical ecosystems and the myriad of benefits they provide to both marine life and human communities. Effective conservation strategies and global efforts to reduce greenhouse gas emissions are essential for the future of coral reefs.

Questions

1. What are the essential services provided by coral reefs as mentioned in the passage?
2. Explain the process and consequences of coral bleaching.
3. How does ocean acidification affect coral reefs?
4. What role do hurricanes and tropical storms play in the health of coral reefs?
5. According to the passage, what measures are essential for preserving coral reefs?

Answers

1. The essential services provided by coral reefs include supporting marine biodiversity, protecting coastlines from erosion, and contributing to local economies through tourism and fishing.
2. Coral bleaching occurs when corals expel the symbiotic algae (zooxanthellae) due to stress from elevated water temperatures. This leads to a loss of color and essential nutrients. If temperatures normalize, corals can recover, but prolonged bleaching can result in coral death.
3. Ocean acidification affects coral reefs by lowering pH levels, making the water more acidic. This hinders the ability of corals to calcify, weakening their structures and increasing susceptibility to erosion.
4. Hurricanes and tropical storms can physically damage coral reefs by uprooting coral colonies and altering habitats necessary for marine life survival.
5. The passage states that effective conservation strategies and global efforts to reduce greenhouse gas emissions are essential for preserving coral reefs.