Earth at an accelerating rate. Importance as a climate change metric Climate researchers Kevin Trenberth, James Hansen, and colleagues have identified the monitoring of Earth's energy imbalance as an imperative to help policymakers guide the pace of planning for climate change adaptation. Because of climate system inertia, longer-term EEI trends can forecast further changes that are "in the pipeline". In 2012, NASA scientists reported that to stop global warming atmospheric CO2 concentration would have to be reduced to 350 ppm or less, assuming all other climate forcings were fixed. As of 2020, atmospheric CO2 reached 415 ppm and all long-lived greenhouse gases exceeded a 500 ppm -equivalent concentration due to continued growth in human emissions. See also Lorenz energy cycle Planetary equilibrium temperature Climate sensitivity Tipping points in the climate system Anthropogenic metabolism References Additional bibliography for cited sources IPCC reports AR5 Working Group I Report (pb: ). Special Report on Global Warming of 1.5 °C Global Warming of 1.5 ºC — . AR6 Working Group I Report External links NASA: The Atmosphere's Energy Budget Clouds and Earth's Radiant Energy System (CERES) NASA/GEWEX Surface Radiation Budget (SRB) Project Atmospheric sciences Climate forcing Climate variability and change Climatology Earth Earth sciences Energy Environmental science Oceanography Articles containing video clips