Describe and explain the causes of El Niño and La Niña
What will be an ideal response?
El Niño and La Niña describe contrasting conditions of surface-water temperature off the western coast of South America. During an El Niño, the water is warmer than normal and during La Niña the water is cooler than normal. These two departures from average conditions result from interactions between wind and ocean circulation. In normal years, easterly trade winds cause ocean currents in the Pacific Ocean that move away from South America, allowing cooler water to rise from depth to the surface. During El Niño years the trade winds are weak and the westward flowing currents cease. This means that tropically heated water remains in the eastern Pacific Ocean and the colder water doesn't upwell from depth. With La Niña conditions, the trade winds are exceptionally strong, and move the upwelling water far across the Pacific Ocean.
You might also like to view...
Olivine is an example of a ferromagnesian silicate mineral. Indicate whether the statement is true or false
Which of the following is true regarding the solubility of gases?
A) Solubility always decreases as pressure increases. B) Solubility always increases as pressure increases. C) Solubility usually decreases as pressure increases. D) Solubility usually increases as pressure increases.
Which of the following features are the two important characteristics of High-latitude climates (Polar and sub-Polar)?
A) low temperatures and sub 25 degrees heat in the summer B) extreme seasonal variability and polar snow storms dumping over 17 inches of snow every month C) low average temperatures and extreme seasonal variability. D) few daylight hours both in the summer and winter E) summer rain and winter dry periods
What happens to wave energy and erosion when riprap or seawalls are installed?
a. ?Waves striking the riprap are reflected back against the incoming waves to lessen their overall effect. b. ?Wave height rises against the wall, and more erosion occurs at the base of the wall. c. ?Seawalls do not influence wave energy or erosion; they only create separation between the sea and structures. d. ?Waves lose their energy against riprap or seawalls, so erosion is prevented in that area. e. ?Waves pulverize the riprap and seawalls, creating sand that helps maintain the beach.