I don't believe that global population growth means that it will eventually oustrip the ability of the countries to provide for the extra people. While climate change and global warming are alarming and threatening our water resources for example, I believe that with the right social system that more and more people are demanding including in the US the past despoiliation of the earth by profit hungry corporations this behaviour can become a thing of the past if enough people oppose it.
The global population will increase significantly in the future, creating many megacities predominantly in Asian countries. Population growth is significant in LICs especially in Africa, Asia and South America.
They are brought from colder regions e.g. the North and South poles where ice caps are melting to give cold water. Currents are due to the effect of wind on the water.
