chapter 14 -Critical thinking

3. There are only a few reefs off the northeast coast of Brazil, even though it lies in the tropics. How would you explain this?

-Reef corals are limited to warm water and can grow and reproduce only if the average water temperature is about about 20^oC (68^oF). Most reefs grow in considerably warmer areas. Water is too warm is also bad for corals. The upper temperature limit varies, but is usually around 30^oC to 35^oC (86^oF to 95^oF). According from the page of 304 we can see the map of Brazil is between 30^o to 60^oalthough which is close to the average 20^o isotherm. Reefs off the northeast coast of Brazil have been less because affected the water temperatures reached 29.5^oC on the bottom of these reefs at 9–12 m. That’s the reasons why only a few of reefs are off the northeast coast of Brazil.