Despite the expansion of green mandates across the investment chain, definitions of some of the asset classes associated with green investing are ambiguous and poorly defined. The EU taxonomy for sustainable activities is a promising step in the right direction. For example, a 'green' label for bonds is often stretched to encompass financing facilities of issuers that misrepresent the actual environmental footprint of their operations . Even in cases where the bonds' proceeds are actually used to finance green projects, investors often remain exposed to both the green and 'brown' assets of the issuers . The heterogeneity of metrics and rating methodologies  results in inconsistent and unreliable quantification of the actual environmental footprint of corporate and sovereign issuers .
IPCC
Climate Change 2022: Impacts, Adaptation and Vulnerability
IPCC Report