The CSIRO will split its climate science into two, creating a special unit based in Hobart but leaving in doubt the future of at least 50 climate researchers.

A new CSIRO Climate Science Centre, foreshadowed by Fairfax Media, will coordinate the work of 40 scientists carved out of existing CSIRO teams, and also tap into work by the Bureau of Meteorology and universities.

However, a separate email sent to staff on Tuesday morning shows the Oceans and Atmosphere division which houses the main climate modelling and monitoring units will shed about 75 of its 140 staff.

Of these 75, 13 will be in the Ocean Climate Dynamics and 32 in the Earth System Assessment unit, which house the ACCESS climate model work and that of Cape Grim's monitoring site.

In the email, chief executive Larry Marshall said the agency's executive had used "feedback" on the planned  cuts to lower the total number of jobs to go from across the agency to 275 rather than the original 350.

"To achieve this change, we won't be able to make as many new recruitments in the areas as previously planned," Dr Marshall said."Our goal is still for our staffing numbers to return to the current level, but it will take us longer to achieve."

The staff reductions now planned are in Minerals (about 35), Land and Water (about 70), Agriculture (about 30), Manufacturing (about 45), Oceans and Atmosphere (about 75) and Food & Nutrition (about 20), the email to staff said.

While the CSIRO described the new climate science centre as a "win" because it would secure decade-long funding, the reaction from within was dismissive.

"It looks like a con," a senior CSIRO climate researcher told Fairfax Media. "Once again, there was no consultation with staff. The plan is to separate the climate scientists into two lots. What are they planning to do with those left out of the centre?"

'Political science'

CSIRO and the Turnbull government have been under pressure since early February to explain why the science agency was planning to cull as many as 110 of its 140 staff within the Oceans & Atmosphere division.

The cuts, which have been pared back after complaints from partner agencies, were part of a plan by Dr Marshall to shed 350 jobs and re-hire a similar number over two years in areas deemed to be more promising for external revenue.

Environment Minister Greg Hunt said CSIRO was an independent agency but added that the government and Chief Scientist Alan Finkel had to intervene "to help broker" a resolution.

"From what was frankly a difficult situation, we worked to engage with the organisation and, I think, to get the longest, deepest national climate program that Australia has ever had," Mr Hunt told ABC Radio.

Labor's shadow industry minister Kim Carr said the new centre appears to be aimed at heading off another damning senate committee hearing on Wednesday.

Dr Marshall was due to attend, along with three other executives, but chairman David Thodey was also due to make his first appearance. Mr Thodey has asked for his evidence to be made in camera and without accompaniment from CSIRO management, Fairfax Media understands.

"The only thing scientific about the new centre is political science," Senator Carr said. "It's been cobbled together as a means to save marginal seats [in Tasmania]. I call on the government to halt the job cuts to CSIRO pending the election."

Independent panel

Dr Marshall said Tuesday's announcement was "a culmination of the ongoing consultation and feedback we've had from our staff and stakeholders, and this new Centre is a reflection of the strong collaboration and support right across our system and the global community".

The response to the original plan to gut climate science at the agency drew criticism from more than 3000 scientists internationally.

The urgency of understanding how fast the climate is changing has been fuelled by record global heat so far in 2016 as the ebbing giant El Nino event in the Pacific adds to the background warming.

Science Minister Christopher Pyne welcomed the new centre and said the creation of a separate independent National Climate Science Advisory Committee to inform ministers of climate developments was another plus.

"[The new panel] would boost collaboration and its advice will be important to both operational and future policy decisions," Mr Pyne said in a statement.

Chief Scientist Dr Finkel said the creation of a national climate research centre was "the right move for Australia".

"The new centre is a stable building block in this critical field, which will both inform national policy and meet our international obligations," Dr Finkel said in a statement.

"Australia has a central role to play in understanding the climate of the Southern Hemisphere.

Adam Bandt, the Greens spokesman for science, said the new centre appeared to be a "sleight of hand" aimed at easing some of the pressure "they've been feeling from the public and respected scientific organisations across the world".

"The government cannot wash their hands clean of these devastating cuts to the CSIRO. Malcolm Turnbull and Christopher Pyne must intervene and save all the jobs set to be cut from the CSIRO before it's too late," Mr Bandt said.