The long-term, and what many say is somewhat unrealistic, goal of the Paris climate agreement ratified last year is to achieve zero global greenhouse gas emissions latest by 2080. Doing so, climate scientists argue, is a crucial prerequisite to limiting the rise in global temperatures to within 2 degrees Celsius (3.6 degrees Fahrenheit) above preindustrial levels.

Now, in an article published Friday in the journal Science, a team of climate scientists has outlined a new pathway for achieving net zero emissions even sooner — by 2050. The authors of the proposal say this can be done through a two-pronged approach — one that involves creating a “carbon law” that sees carbon emissions halving every decade, and simultaneously doubling renewables in the energy sector every five to seven years.

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“The carbon law outlines a global path towards achieving climate and sustainability goals in broad yet quantitative terms. It sketches a general vision of rapid emission reductions in conjunction with the development of sustainable carbon dioxide removal options,” co-author Joeri Rogelj from the International Institute for Applied Systems Analysis in Austria said in a statement. “It clearly communicates that no single solution will do the job, and that this deep uncertainty thus implies starting today pursuing multiple options simultaneously.”

The world currently produces 40 gigatons of carbon dioxide every year, according to the National Oceanic and Atmospheric Administration. Under the proposed plan, this would drop to 24 gigatons by 2030, 14 gigatons by 2040, and 5 gigatons by 2050 — at which point, improvements in carbon capture technologies would lead to zero net emissions.

So how would this be achieved? The first step would be to implement what the authors called “no brainer” policies by 2020, which include, among other things, ushering in carbon tax schemes and cap-and-trade systems, and eliminating fossil fuel subsidies.

This, however, is easier said than done. The two countries that cumulatively account for over 40 percent of the world’s greenhouse gas emissions — the United States and China — have been quite resistant to the idea of imposing a carbon tax, and a White House spokeswoman recently confirmed that President Donald Trump “is not considering a carbon tax.”

The next phase (2020 to 2030) would require coal and other polluting source of fuel to be phased out, coupled with a drastic increase in public and private investment in research and development for climate solutions — making this decade one that would require, in the words of the authors, “Herculean efforts.”

In the two decades that follow 2030, the study’s authors envisage complete electrification of all sectors in countries like Norway, Denmark and Sweden, increasing the global share of carbon-neutral fuels, and development of “radical” new energy generation solutions.

“By 2050, the world will have reached net zero CO2 emissions, with a global economy powered by carbon-free energy and fed from carbon-sequestering sustainable agriculture. Meanwhile, BECCS [bioenergy carbon capture and storage] schemes have been scaled up and draw down >5 GtCO2/year,” the researchers wrote.

The ambitious proposal comes at a time when the world, according to the World Meteorological Organization, has entered a “truly uncharted territory,” with rising carbon emissions inexorably raising sea levels and global average temperatures. 2016 — a year that was warmest ever recorded — also witnessed a record number of extreme weather events, and record low sea ice cover in both the poles.

“We cannot predict where civilization will be mid-century, but a decadal staircase based on a carbon law, if adopted broadly, may provide essential economic boundary conditions to make a zero-emissions future an inevitability rather than wishful thinking,” the authors of the study concluded.