La-Nina is a climate pattern that occurs in the Pacific Ocean and is characterized by cooler-than-normal sea surface temperatures. Therefore, option 2, "Cools downs the temperature of water," is the correct answer. This cooler water affects various aspects of the Pacific Ocean ecosystem. It can lead to changes in weather patterns, including increased rainfall in some regions and droughts in others. Additionally, La-Nina can influence ocean currents, which can impact marine life and nutrient availability. However, it is important to note that La-Nina does not directly affect the salinity of the ocean. Salinity refers to the concentration of salt in seawater and is typically influenced by factors such as evaporation, precipitation, and river runoff. So, option 1, "Decreases salinity of ocean," is incorrect.