The CSIRO will cut more than 30 jobs from its Marine and Atmospheric Research (CMAR) division over the coming weeks.

In a letter to the CSIRO Staff Association, management states that it will cut 31 full-time equivalent positions, the vast majority of them research scientists.

The CMAR division has previously had about 550 staff located across Victoria, the ACT, Tasmania, Western Australia and Brisbane.

It's research aims to advance Australia's climate, marine and earth systems science and covers topics including coastal modelling and ocean climate processes.

The staff association's acting secretary, Doctor Michael Borgas, says 18 jobs will go from the Hobart office while eight positions will be cut from the Aspendale laboratory in Melbourne.

He says it puts the long-term assessment of the sustainability of Australia's oceans, atmosphere and climate at risk.

"As much as possible, CSIRO managers are trying to hold on to capabilities so it can be restarted at some point in the future, so some of the work won't be lost completely," he said.

"But nevertheless, there is less science and knowledge gathering that informs decisions around our climate, our atmospheric environment, our fish stocks and marine reserves.

"So that (lack) of information could lead to severe (poor) judgments being made on development."

Following the Federal Budget, the CSIRO will lose $116 million in funding over four years. More than 500 jobs, about one tenth of the organisation's workforce, will go.

Dr Borgas says there is a 'nervous climate' amongst staff as they await further details of job cuts, including in the agriculture and mining research sectors.

"Certainly there are job cuts in almost all of the organisation, and in particular in these current cuts where it's hitting hardest in Tasmania.

"We also expect there to be cuts in information sciences that are co-located with the marine scientists down in Hobart."

A spokesperson for the CSIRO said the organisation will continue to support the management of Australia's ocean territories and coasts and continue to deliver 'excellence in science', especially in co-ordination with its partners in fisheries.

"CSIRO remains committed to our internationally recognised research which enhances our understanding of Australia's weather and climate. We will be integrating some climate research currently delivered across several parts of the organisation."