All journals provide 10% of the previous year's page budget to be assigned to authors lacking support of funds. Before applying for a waiver, all authors are requested to explore funding options at their own university. Some research funders have established general APC funding schemes, like the Research Council UK. There, a block of funding has generally been allocated to each university to cover open-access publication costs associated with Research-Council-funded grants and research students. However, if the authors are not eligible for any financial support scheme, they are asked to contact Copernicus Publications Editorial Support (editorial@copernicus.org) after their manuscript has been accepted for publication to apply for a partial or full waiver. Applications should state why the author (or any of the co-authors) cannot pay the charges. Applications by students or post-doctoral researchers also require a brief statement of their supervisor or group leader. Applications will be granted if supported by the handling editor and approved by the chief editors. In special cases, such as long review manuscripts, the authors may contact the chief editors prior to manuscript submission.