For monetary policy, however, they are akin to a series of persistent positive supply shocks that may force central banks into action should these shocks cause a more general and broad-based reappraisal by the public of the medium-term inflation outlook.21  Greening monetary policy implementation So, the implications for the conduct of monetary policy could be substantial. The question, then, is whether central banks themselves should be doing more to prevent climate change in the first place.22 Some argue we have an obligation to act, since the EU Treaty states that “without prejudice to its primary objective, the ECB shall support the general economic policies in the Union”, which include a high level of protection and improvement of the quality of the environment, and mandates environmental protection requirements to be integrated into the definition and implementation of the Union's policies and activities.23 Certainly, the protection of the environment is not the only transversal objective assigned to EU institutions and hence to the ECB. Under the Treaty one could equally ask, for example, why the ECB should not promote industries that promise the strongest employment growth, irrespective of their ecological footprint.24 But equally importantly, the ECB is subject to the Treaty requirement to “act in accordance with the principle of an open market economy with free competition”. In the end, the Treaty grants the ECB a high degree of independence and it enjoys broad discretion in implementing its policies.
17 This is despite oil price shocks having had on average much less impact on the economy, largely thanks to the  8/9  BIS central bankers' speeches  enhanced credibility central banks have gained over time. See, for example, Choi et al. (2017), “Oil Prices and Inflation Dynamics: Evidence from Advanced and Developing Economies”, IMF Working Paper No 17/196. 18 See, for example, Bielen et al. (2017), “The Future of Power Markets in a Low Marginal Cost World”, Resources  for the Future Working Paper 17–26; and Archer, C. and M. Z. Jacobson (2005), “Evaluation of global wind power”, Journal of Geophysical Research, Vol. 110, pp. 1-20. 19 See, for example, the Platform for Climate Adaptation and Risk Reduction on www.placard-network.eu. 20 Google, for example, managed to reduce its energy consumption by more than a third by optimising its cooling  system through artificial intelligence controlled systems. 21 On the positive side, however, the associated increase in the economy’s trend growth rate will help lift the  natural rate of interest, thereby increasing the policy space available for central banks to manage fluctuations in the business cycle. See also Cœuré, B. (2018), “Scars that never were? Potential output and slack after the crisis”, speech at the CEPII 40th Anniversary Conference, Paris, 12 April. 22 See the European Parliament resolution of 29 May 2018 on sustainable finance (2018/2007(INI)). 23 See Articles 11 and 127(1) TFEU and Article 3 TEU.