Climate change is the topic of the day. The World Meteorological Organization tells us that the 2011-20 decade was the warmest on record. Earlier this year, the U.S. government re-joined the Paris Accord, and is proposing a range of new programs to mitigate the long-run impact of climate change. Now that a warming planet has made the Arctic increasingly navigable, national security specialists are concerned about geopolitical risks there. Thousands of economists have endorsed a carbon tax. Even central banks have joined together to form the Network for the Greening of the Financial System—a forum to discuss how to take account of climate change in assessing financial stability.
Against that background, last month, NYU Stern’s Volatility and Risk Institute (VRI) held a conference on finance and climate change. Speakers addressed issues ranging from the modeling and measurement of climate risk in finance to assessing its impact on the resilience of the financial system. In this post, we primarily focus on one of the central challenges facing policymakers and practitioners: what is the appropriate discount rate for evaluating the relative costs and benefits of investments in climate change mitigation that will not pay off for decades? We also comment briefly on several other issues in the rapidly growing field of climate finance research.
Past responses to the discount-rate question vary widely. Some observers call for a discount rate matching the high expected return on long-lived, risky assets—a number as high as 7%. This would imply a very low present value of benefits from investments to mitigate climate change, consistent with only modest current expenditures. Others postulate that climate change could lead to the extinction of humanity. For plausible discount rates, the specter of a nearly infinite loss means that virtually any level of mitigation investment is warranted (see, for example, Holt).
Recent climate finance research that we summarize here comes to the conclusion that over any reasonable horizon, the appropriate discount rate for computing the net present value of investments in climate change mitigation should be relatively low….
The Federal Reserve’s annual stress test is the de facto capital planning regime for the largest U.S. banks. Not surprisingly, it comes under frequent attack from bank CEOs who argue, as Jamie Dimon recently did, that “banks have too much capital…and more of that capital can be safely used to finance the economy” (see page 22 here). From their perspective, this makes sense. Bank shareholders, who the CEOs represent, benefit from the upside in good times, but do not bear the full costs when the financial system falters. As readers of this blog know, we’ve argued frequently that capital requirements should be raised further in order to better align banks’ private incentives with those of society (see, for example, here and here).
A more compelling criticism of central bank stress tests focuses on their discretionary character. To the extent feasible, central banks should minimize their interference in the allocation of resources by private intermediaries, allowing them to direct lending to those projects deemed to be the most productive.
But the painful lessons that have come from large asset price swings and high concentrations of risk provide a strong case for the kind of limited discretion that the Fed uses in formulating its stress tests. This blog post highlights why it makes sense for regulators to use this year's stress test exercise to learn how well the largest U.S. intermediaries would fare if the recent commercial real estate price boom were to turn into a bust....
When President Nixon and Chairman Mao shook hands in Beijing in 1972, only 17% of the 862 million Chinese lived in urban areas and the entire stock of housing was state owned. Today, more than half of China’s 1.4 billion residents live in cities, while 9 out of 10 households own their homes. Unsurprisingly, this housing revolution has brought with it a property price boom. Over the past decade, urban land prices have risen more than four-fold, with high flyers like Beijing surging by a factor of more than 10 (for the data, see here).
Will China follow the same path the U.S. took in the last decade? Will China’s boom turn into a bust?...
In the 30 months following the 2000 stock market peak, the S&P 500 fell by about 45%. Yet the U.S. recession that followed was brief and shallow. In the 21 months following the 2007 stock market peak, the equity market fell by a comparable 52%. This time was different: the recession that began in December 2007 was the deepest and longest since the 1930s.
The contrast between these two episodes of bursting asset price bubbles ought to make you wonder. When should we really worry about asset price bubbles? In fact, the biggest concern is not bubbles per se; it is leverage. And, surprisingly, there remain serious holes in our knowledge about who is leveraged and who is not.
