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Is climate action a lost cause? The United States is from the Paris Agreement for the second time, while heat records over land and sea and extreme weather events have multiplied.

In late 2015, nations agreed through the Paris Agreement to try to hold warming well under 2°C and ideally to 1.5°C. Almost 10 years later, cutting emissions to the point of meeting the 1.5°C goal very difficult.

But humanity has shifted track enough to avert the worst climate future. Renewables, energy efficiency and other measures have shifted the dial. The of expanded coal use, soaring emissions and a much hotter world is vanishingly unlikely.

Instead, the Earth is tracking towards around 2.7°C average warming by 2100. That level of warming would represent "" for life on this planet. But it shows progress is being made.

How did we get here?

Global greenhouse gas emissions have risen since industrialization began around 1850. Carbon dioxide (CO₂) is far and away the most common greenhouse gas we emit, while methane and nitrous oxide also play a role. These gases trap the sun's heat in the atmosphere, preventing it from radiating back out to space.

In , 41% of the world's energy-related CO₂ emissions came from coal, mainly for electricity generation. Some 32% came from burning oil in road vehicles, and 21% from natural gas used for heating buildings and industrial processes.

The world is certainly feeling the effects. The World Meteorological Organization confirmed 2024 was the , temporarily hitting 1.5°C over the pre-industrial era. In turn, the lethal heat waves, devastating floods and intense cyclones.

How are we tracking?

In 2014, the world's peak body for assessing climate science—the Intergovernmental Panel on Climate Change—began using four scenarios called Representative Concentration Pathways (RCPs). These four big picture climate scenarios are based on what actions humanity does or doesn't take. They comprise:

• rapid climate action, low emissions (RCP 2.6)
• two scenarios of some action and medium emissions (RCP 4.5 and 6.0)
• no action, high emissions (RCP 8.5).

The numbers refer to how many more watts of heat strike each square meter of the planet.

Of these four, only the RCP 2.6 scenario is compatible with the Paris Agreement's goal of holding climate change well under 2ËšC.

But the Earth is tracking towards somewhere between RCP 2.6 and 4.5, which would translate to about by 2100.

IPCC experts five pathways of possible social, economic and political futures to complement the four scenarios.

Of these pathways, we are tracking closest to a scenario where development remains uneven, the intensity of resource and energy use declines, and population growth levels off.

While effective, these scenarios are now more than a decade old and need to be updated. In response, my colleagues and I produced the to outline rapid pathways to decarbonize. We set an ambitious carbon budget of 450 gigatons of CO₂ before reaching net zero—a pathway even more ambitious than the RCP 2.6.

The US, European Union and China together represent about 28% of the global population, but are responsible for 56% of (926 gigatons) . The pathways compatible with 1.5°C give them a remaining carbon budget of 243 Gt CO₂. China would require the largest carbon budget to reach decarbonization.

For this to happen, by 2050, the world would have to be 100% powered by clean sources and phase out fossil fuel use. This would limit global warming to around 1.5°C, with a certainty of just over 50%. We would also have to end deforestation within the same timeframe.

Emissions peak—are we there yet?

Emissions of carbon dioxide and other greenhouse gases have still not plateaued, despite sharply increasing renewable electricity generation, battery storage and lower-cost electric vehicles.

But there has been real progress. The EU says its emissions in 2023 compared to 2022. Europe's net emissions are now 37% below 1990 levels, while the region's GDP grew 68% over the . The EU remains on track to reach its goal of reducing emissions by at least 55% by 2030.

Australia's emissions fell by 0.6% . The country is now 28.2% below June 2005 levels, which is the set for its Paris Agreement goal of a 43% reduction by 2030.

In the US, emissions below pre-pandemic levels and remain about 20% below 2005 levels. Since peaking in 2004, US emissions have trended downward.

The world's largest emitter, China, is finally cutting its emissions. Huge growth in renewables has now led to the on record, despite surging demand for power. This is good news. For years, China's domestic emissions remained high despite its leading role in solar, wind, EVs and battery technology.

China produces almost one-third of the world's energy-related carbon emissions—not least because it is the workshop of the world. Every cut China makes will have a major global effect.

According to the , limiting warming to around 1.5°C requires global emissions to peak before 2025 at the latest. It now looks like the peak this year.

Despite daily negative news, the decarbonization train has left the station. In 2024, renewables accounted for more than in electricity production globally. Electric vehicles became cost-competitive, while are developing fast and solar is on a .

So, is it too late to save the climate? No. The technologies we need are finally cheap enough. The sooner we stop climate change from worsening, the more disasters, famine and death . We might not manage 1.5°C or even 2°C, but every tenth of a degree counts. The faster we make the shift, the better our climate future.

This article is republished from The Conversation under a Creative Commons license. Read the original article.