Efforts to create so-called green jobs need to intensify if the UK government is to achieve its target of two million roles by 2030, according to a report.
Jobs linked to the green economy accounted for 1.2% of all advertised roles in the year to July 2021, consultancy PwC said.
That equates to just 124,600 new jobs.
Boosting green job creation is part of the government's "green industrial revolution" plans.
In November 2020, the government announced £4bn would be spent as part of its plans to create two million green jobs by 2030.
The COP 26 summit held in Glasgow a year later has put the issue into sharp focus again.
But there are concerns that the green jobs transition could pose some risks, as it will have an impact on traditional jobs, especially in polluting industries.
In September, the Trade Union Congress (TUC) warned up to 660,000 jobs could be at risk if the UK fails to reach its net-zero target as quickly as other nations.
What is a green job?
The simplest answer is a job that directly contributes to tackling climate change, although many think it should also cover roles that indirectly support that ambition.
Growing sectors where one might find more green jobs being advertised include low-carbon farming, heating without emissions, and wind turbine maintenance.
In its research, PwC said jobs that support the green economy indirectly should also be considered green.
Such roles might include environmental advisers or experts in environmental or sustainability research and education.
PwC's report said work was needed to ensure the move to a net-zero economy does not add to regional inequalities.
It found that Wales, Northern Ireland and Yorkshire and the Humber lagged behind other parts of the UK in terms of transitioning to a greener economy. Scotland and London were the top performers, according to the research.
PwC ranked areas in terms of how they performed in job creation, the benefits of green jobs, the loss of "sunset jobs", the carbon intensity of employment, and green workplaces.
They hunted for online job ads that mentioned things like sustainability and environment - there had to be a number of mentions.
Kevin Ellis, PwC chairman and senior partner, said: "Jobs are getting greener and this is cause for optimism, but evidence is needed on the level and distribution of these opportunities.
"Left unchecked, green employment will grow in the most fertile spots, but not necessarily where they're needed most.
"By acting now, we have a massive opportunity to rebalance the economy and ensure a fair transition."
A government spokesman told the BBC: "As this data shows, hundreds of thousands of green jobs are being created across the country, and our landmark Net Zero Strategy sets out how the UK will accelerate this growth, unlocking £90bn in private investment.
"Our plans will see the majority of new green jobs to be created and supported outside London and the south east, with our shift to a low carbon economy providing an unprecedented opportunity to attract new, future-proof businesses in our industrial heartlands."