Bjorn Lomborg's argument that it is wasteful to spend money implementing the Kyoto Protocol is flawed because it inappropriately uses cost-benefit analysis ("$50 billion: how would you spend it?", February 4).
CBA heavily penalises projects that cost a lot in the near future and generate benefits only in the longer term, such as tackling climate change. This does not make them, as he would have it, inherently "bad projects".
Conversely, CBA over-favours projects that cost little now even though they may have serious adverse long-term consequences, such as not tackling climate change. This is because those adverse effects that occur well into the future are so heavily discounted that they barely impinge on immediate satisfactions. CBA assumes that anything happening beyond the arbitrary final year is of zero concern.
Policymakers who resort to CBA leave themselves wide open to undertaking irresponsible strategies that are profitable in the immediate term but not viable in the long run.
Nick von Tunzelmann
Science and Technology Policy Unit
Sussex University