How do heat waves, cold waves, droughts, hail and tornadoes affect US agriculture?

A very first draft of a new paper on climate extremes available here. Still preliminary and incomplete.

Presented today at the ASSA meetings in San Francisco. Presentation available here.

Abstract:

We estimate the impact of extreme events on corn and soybeans yields, and on agricultural land values in the Eastern United States. We find the most harmful event is a severe drought but that cold waves, heat waves, and storms all reduce both corn and soybean yields. Over 80% of the damage from extreme events is caused by droughts and cold waves with heat waves causing only 6% of the damage. Including extreme events in a panel model of weather alters how temperature affects yields, making cold temperature more harmful and hot temperatures less harmful. Extreme events have no effect on farmland values probably because American farmers are buffered from extreme events by subsidized public crop insurance.

Keynote at final meeting of Global-IQ Project

The keynote presentation that I gave at the final meeting of the EU FP7 project Global-IQ is available here.

The objective of the GLOBAL IQ project was three-fold:

• to provide significant advances in the estimation of socio-economic impacts of global challenges – at Global, European and regional scale;
• to identify optimal adaptation strategies;
• to evaluate total costs and the optimal mix of adaptation and mitigation against global changes.

Led by Toulouse School of Economics, the Global IQ project involved eleven partners located in eight EU members states:

• Toulouse School of Economics (TSE) France
• Fondazione Eni Enrico Mattei (FEEM) Italy
• Internationales Institut für Angewandte Systemanalyse (IIASA) Austria
• Potsdam-Institut für Klimafolgenforschung (PIK) Germany
• University of Gothenburg (UGOT) Sweden
• Charles University in Prague (CUNI) Czech Republic
• Istituto di Studi per l’Integrazione dei Sistemi (ISIS) Italy
• London School of Economic (LSE) UK
• Graduate Institute of International Studies in Geneva (HEID) Switzerland
• Centre for Economic Policy Research (CEPR) UK

Do Temperature Thresholds Threaten American Farmland?

On January 4 I presented the paper titled "Do Temperature Thresholds Threaten American Farmland?" joint with Robert Mendelsohn at the ASSA meetings in Philadelphia.

The presentation is available here.

In short:

In this paper we use flexible functional forms to estimate the marginal effect of mean temperatures during 3-hour, daily and longer time intervals on land values. We use US Agricultural Census Data and detailed climate data obtained from the NARR model, a very large dataset that contains climatic data on 3-hour time intervals, at fine spatial resolution, from 1979 to present day. The paper finds no evidence of temperature threshold effects on land values and in the Eastern United States. The flexible functional forms suggest inverted-U shaped or almost constant marginal effects at different levels of temperature whether one is using average temperature over 3-hour, daily, continuous days or the growing season. We find instead evidence that land values in areas that are frequently affected by extreme heat waves reflect large expected productivity losses. Using annual yields and weather data we find evidence that both cold and high temperatures reduce corn, soybeans, and to a lesser extent, cotton yields. The downward sloping section of the relationship that relates temperature and yields is steeper than the upward sloping section but we do not find evidence of sudden discontinuities.

First Lead Author Meeting of IPCC AR5 WGIII

I just returned from the first Lead Authors meeting of the International Panel on Climate Change (IPCC) Working Group III in Changwon, South Korea. This was the first of a series of meetings that will serve to prepare the Fifth Assessment Report (AR5). The next meeting will be in New Zealand in Spring 2012. The AR5 will be ready in 2014.