The California Air Resources Board approved last week the Climate Action Registry and the American Carbon Registry to help evaluate compliance-grade carbon offsets under the state’s cap and trade program. It has accredited trained third-party verifiers to help evaluate the quality of offset projects submitted for approval. The two registries may now issue compliance credits covered entities may use under the economy-wide trading program to meet declining annual emissions caps. The board has approved accounting protocols for forestry, urban forestry, diary manure digesters, and the destruction of ozone-depleting substances.