Humans are pumping more carbon dioxide into the atmosphere at an accelerating rate. But climate change is a cumulative problem, a function of the total amount of greenhouse gases that have accumulated in the sky.

from https://www.vox.com/energy-and-environment/2019/4/24/18512804/climate-change-united-states-china-emissions
https://cdn.vox-cdn.com/thumbor/dXFN0WPqHghkqovSkZUNqpL_Grw=/0x0:2261×1565/1200×0/filters:focal(0x0:2261×1565):no_upscale()/cdn.vox-cdn.com/uploads/chorus_asset/file/16185122/gw_graphic_pie_chart_co2_emissions_by_country_2015.png