Feedbacks can be positive or negative , vary spatially and seasonally, and act over large geographic areas and long time periods , making them difficult to observe and quantify directly . Due to the positive impacts of CO2 on vegetation growth and ecosystem carbon storage   , the associated climate feedback is negative . By contrast, projected global losses of carbon in warmer climates  imply a positive climate feedback. WGI  assesses an overall increase in land carbon uptake through the 21st century. However, the overall strength of the carbon cycle-climate feedback remains very uncertain. One of the underlying reasons may be complex interactions with ecosystem water balance and nitrogen and phosphorous availability, which
IPCC
Climate Change 2022: Impacts, Adaptation and Vulnerability
IPCC Report