One may be rich and have all the material riches in the world, but these aren't skin-deep. They only "bring the illusion of happiness," Pope Francis told the more than one million youth contingent who braved the rains and flocked to the Copacabana beach for the World Youth Day 2013 festivities on Thursday.

Pope Francis, who started his Thursday morning visiting Brazil's poorest before capping it on the glitzy beach of world-famous Copacabana, one of the world's most exclusive enclaves, he urged all the people present to not let "selfishness and individualism" trample what could be a "culture of solidarity."

"No-one can remain insensitive to the inequalities that persist in the world," he said.

"This week, Rio has become the center of the Church, its heart both youthful and vibrant, because you have responded generously and enthusiastically to the invitation that Jesus has made to you to be with Him and to become His friends."

Pope Francis who has an affinity serving the poor, is known for his frequent visits into the slums near Buenos Aires even when was still a humble cardinal. And this strongly manifested on Thursday morning when he looked visibly overjoyed with the close contact with the residents of Manguinhos, a sprawling shantytown overrun by violence and controlled by drug lords.

Read more: World Youth Day 2013: Younger Security Aides Hardly Coping with Energetic 76-year-old Pope Francis

"Everybody, according to his or her particular opportunities and responsibilities, should be able to make a personal contribution to putting an end to so many social injustices," Pope Francis told listeners present on a muddy, rain-drenched soccer field next to a river smelling of sewer water.

"I would like to make an appeal to those in possession of greater resources, to public authorities and to all people of good will who are working for social justice: never tire of working for a more just world, marked by greater solidarity!" he said.

Pope Francis also said no pacification of the poor as well as no harmony and happiness will last and succeed "in a society that ignores, pushes to the margins or excludes a part of itself."

On Thursday, Rio and Copacabana beach experienced one of its coldest and wettest winter days. Yet, Pope Francis thanked everyone profusely for being there.

"I've always heard that Cariocas (Rio-born people) did not like the cold or the rain. But you are here. Well done!" Pope Francis even joked at the start of his address.