not your average climate change rally but an event that will future performances by usher, no doubt. it is the global citizen 2015 earth day rally. msnbc thomas roberts is live on the mall getting ready for the program to begin. it sounds like a big day ahead. tell us what s in store. reporter: it is going to be a big day and a beautiful day. it s absolutely fantastic. you were talking about thousands, will be here. they re estimating about 250,000 plus people are going to turn out for this free and incredible event that is a combination between the global poverty project and the earth day network. now, our buddy at the global poverty project, the ceo, he said all he wanted was the sun to shine. boy do we have the sun shining. it will be about 80 degrees here. they re just putting the finishing touches on the stage. it was just monday at 12:01 a.m.