The ENDS Guide to Carbon Offsets points buyers towards 30 offset providers world-wide that show strong commitment to delivering quality carbon offsets, nine of which are London-based.

The publication also outlines what buyers should avoid when looking into offset schemes.

This includes offsets from tree-planting (forestry) schemes. Although future schemes to avoid deforestation could become acceptable, about half of all retail offset providers operating currently sell only or mainly credits from tree-planting.

The guide also recommends avoiding New South Wales Greenhouse Gas Abatement Scheme credits (NGACs) and project-based voluntary emission credits (VERs) without third party verification.

The guide names MyClimate based in Switzerland, Atmosfair in Germany, and Offset the Rest in New Zealand, as the top three providers with the highest commitment to offset carbon quality.

It identifies Europe as the global centre of quality carbon offset providers, with 25 of the guide's top 30 based or active there.

In addition, the guide explains the basics of carbon offsetting and features a DIY system for scoring carbon offsets according to their carbon and broader sustainability quality.

The ENDS Guide to Carbon Offsets author Tejas Ewing said: "Carbon offsetting has faced enormous criticism, but has a continuing and growing role in addressing climate change."

He added: "Continued efforts to develop new and stricter standards for offsetting and offsets will also be vital. However, we believe that certain voluntary offset credits (VERs) already make the grade."