Global Phenomena: Tsunami and Agricultural Transformation

Tsunami: Understanding Ocean's Powerful Waves

A Tsunami (from Japanese tsu meaning "port" or "harbor" and nami meaning "wave," literally "harbor wave") is a series of high-energy waves that occur when a large body of water is displaced vertically by a significant phenomenon.

Causes and Characteristics

It is estimated that 90% of tsunamis are caused by earthquakes, in which case they are more accurately termed tectonic tsunamis. The energy of a tsunami depends on its height (wave amplitude) and speed. The total energy discharged on a coastal area also depends on the number of peaks in the wave train (for example, the 2004 Indian Ocean tsunami had up to 7 peaks).

Impact and Displacement

These waves displace a much greater quantity of water than surface waves caused by wind, leading to devastating coastal impacts.

The Green Revolution: Transforming Agriculture

The Green Revolution is the term used internationally to describe the significant increase in agricultural production that occurred in the 1960s.

Origins and Achievements

This transformation was achieved through the adoption of modern production techniques, specifically:

• Genetic selection of high-yield crop varieties.
• Intensive cultivation of monocultures, enabled by irrigation.
• Massive use of fertilizers, pesticides, and herbicides.

These advancements primarily focused on maize and wheat production. The revolution originated in Mexico and subsequently spread to several other developing countries. Its importance lay in the optimistic prospects it offered for eradicating hunger and malnutrition in these nations.

Productivity Gains

The results in terms of productivity gains were spectacular. In Mexico, for example, wheat production increased dramatically:

• From a yield of 750 kg per hectare in 1950.
• To 3,200 kg per hectare in 1970.

This transformation involved investments of several million dollars.

Challenges and Criticisms

However, the downsides soon became apparent. The Green Revolution faced heavy criticism from various perspectives, including environmental, economic, cultural, and nutritional. Key issues included:

• Unknown and harmful storage problems.
• Excessive costs of seeds and complementary technology.
• Increased technological dependence for farmers.
• Superior adaptation of traditional crops in certain local conditions.
• Emergence of new pests resistant to pesticides.