text: <translate> Umwaka wa 2015 witiriwe igihe cyihindagurika ryikirere; umwaka wa mbere ubwo ubushyuhe bwisi bwagumye kuri dogere 1C hejuru yuko bwari bumeze mbere yiterambere ryinganda. <eng>2015 has been called a tipping point on climate change; the first year where global temperatures stayed at more than 1C above preindustrial levels. 