The Big Lottery Fund has pledged up to £50m to help the "most vulnerable" in England tackle the potential impacts of climate change by 2015.
It has also launched a consultation on how the funding could best be used.
A BLF statement said the fund was needed because vulnerable people, such as older people on low incomes and those with disabilities, might be the "most challenged" by the need to reduce carbon emissions and adapt to new climates.
It said they were more likely to live in low-quality housing, would be worst affected by the impact of floods and heat waves, and would have "fewer resources to reduce their carbon footprint and pay higher fuel bills".
The BLF is holding an event today at the Coin Street neighbourhood centre in London as part of the consultation. It will bring together organisations including the children's charity the National Children's Bureau, government departments and local authorities to discuss how the money could help the vulnerable deal with the impact of climate change.
The BLF will distribute up to £10m of the funding in the next year, with as much as £50m available by 2015.
Dharmendra Kanani, England director at the BLF, said today's event was part of the organisation's "inclusive approach to designing and developing" funding programmes.
He said the event would look at "what a funding opportunity would look like, and what its target would be".
Kanani said funding might be allocated as early as next year, and he was committed to spending £50m by 2015.