Ever since humans started to farm we've been responsible for emitting carbon dioxide to the atmosphere. However, it is the industrial revolution over the last 150 years that has really cranked up our emissions, pushing atmospheric carbon dioxide levels from around 288ppm to over 400ppm today. Throughout this period, natural sinks have worked overtime, absorbing ever more carbon dioxide: without their efforts atmospheric concentrations would be well over 500ppm.

So can natural sinks keep going at this pace as emissions increase, and might they start to relax their efforts if emissions decline? To investigate, Chris Jones from the UK Met Office and his colleagues used Earth system models to study how natural sinks could respond to a low-emissions pathway.

Taking the low emissions "Representative Concentration Pathway 2.6" (RCP2.6), which shows emissions peaking in 2020 then declining gently, the researchers analysed climate model simulations in 50 year chunks, calculating how the balance in carbon dioxide absorption will change. They found that natural sinks will progressively weaken under this low-emissions scenario, mopping up 94ppm of carbon dioxide between 2000 and 2050, then 47ppm between 2050 and 2100, falling to 23ppm between 2100 and 2150, and adding to emissions by 6ppm between 2250 and 2300.

This response is thought to be partly linked to climate change – warmer temperatures and drier weather may make plants more stressed and reduce growth rates, for example – but is mostly due to the amount of carbon dioxide available. "Natural sinks are being driven by the difference between what they hold and the amount in the atmosphere, so if the atmosphere stabilizes or reduces then this driving force diminishes, and possibly reverses itself," said Jones, whose findings are published in Environmental Research Letters (ERL).

The simulations also show how negative emissions technologies such as carbon capture and storage will have to increase their game in order to keep to the idealized scenario. In this case negative-emissions technologies must go from mopping up 14ppm worth of carbon dioxide between 2000 and 2050, to absorbing 73ppm worth of carbon dioxide during every half century from 2100 onwards.

Maintaining this balance is something that needs to be taken into account in climate models, the scientists argue. "The climate doesn’t care, for example, if we emit 10 tonnes and remove 8, or if we just emit 2," said Jones. "The end result is the same. So we need to think about the global total emission – in terms of how society is affected of course, the technology and economic implications of these can be very different."

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• This article was updated on 2/2/2017 to provide links to the correct ERL paper.