Coral Reefs and Climate Change
Impacts on humans



Status of Coral Reefs

Climate Change Threats to Coral Reefs

Impacts on surrounding ecosystems

Impacts on humans




Bio 217 Home | Duke Biology

site created by
Ross Cunning
April 24, 2007


The decline of coral reefs will have many far-reaching impacts on humans. Nearly 500 million people directly depend on coral reefs for food and income (Wilkinson 2004). As coral reefs suffer from global climate change, the people that depend on them will suffer as well. Following are descriptions of some of the major resources and services that reefs provide to humans, and the consequences that will result from their loss.


Reefs, along with the mangrove and seagrass habitats, are the foundation of the high productivity found in the coastal environment. This productivity is relied on significantly by people all over the world. Pacific Islanders are especially dependent on reefs, as at least 90% of their animal protein comes from coastal marine resources (Birkeland 1985). Globally, reef-related fisheries constitute 9-12% of the total fish catch, and in many areas in the Indo-Pacific it is up to 25% (Moberg & Folke 1999). These fisheries are important not only for the food they provide, but also for their economic value. In Australia, Great Barrier Reef fisheries generate US$125 million annually (GBRMPA 2005). For Southeast Asia, the potential sustainable fisheries benefit is US$2.4 billion (Burke et al. 2002). In addition, a one billion dollar per year industry has arisen in Southeast Asia around the live fish food trade (Wattern-Rhodes 2003). Although unsustainable as it is, the further decline of coral reefs will destroy this economically important industry. Reef fish are also valuable as ornamentals for aquarium collection. Live fish for this market generate about 20 to 40 million dollars per year (Moberg & Folke 1999). Thus, the decline of coral reef fish will be followed by a decline in economies based on them.

The most significant economic value of reefs may lie in their potential for tourism. Tourism can be a sustainable, non-consumptive use of reef resources that has the potential to generate large amounts of money. For small island developing states, ecotourism based on healthy coral reefs may provide the best opportunity to develop sustainable economies (Wilkinson 2004). In Australia, tourism on the Great Barrier Reef generates US$4.26 billion annually (GBRMPA 2005). In the Caribbean region, tourism is expected to generates US$56.1 billion in 2007, and grow to $107.3 billion by 2017. The industry also employs almost 2.5 million people in the Caribbean, which is about 15% of total employment in the region (WTTC 2007). Without reefs, this industry would significantly decline. Not only do reefs contribute directly to this industry through reef tourism, but they are also responsible for generating the fine coral sand that supplies tropical beaches, which are one of the main tourist attractions in tropical regions (Moberg & Folke 1999). Reef-based tourism is especially important in many tropical island developing nations, as they have few or no other resources. Loss of coral reefs will therefore ruin the basic economic support of these nations (Wilkinson 2004).

Reefs also protect coastlines from ocean currents, waves, and storms. This is a very important service, considering the amount and value of coastal development in tropical regions. It is estimated that over a 25-year period in Indonesia, coral destruction was responsible for the loss of between US$820 and 1 million per kilometer of coastline (Moberg & Folke 1999). The protection from coral reefs also played a large part in reducing the impact of the tsunami in Southeat Asia in December 2004 (Royal Society 2005).

Many important pharmaceutical chemicals have been found on coral reefs (Moberg & Folke 1999), including useful anti-inflammatory and anti-coagulating substances, and some for treating cancer and AIDS. Many more have yet to be found, and may never be found if reefs decline due to climate change.

Coral reefs also serve as an important source of historical information to scientists. Reefs are built by continuous deposition of calcium carbonate, and thus they are made up a many layers that contain fingerprints of oceanic and atmospheric chemistry and past climatic conditions (Moberg & Folke 1999).


Photo credits:
Coral core: NOAA
Others: Andy Lewis