How Econometrics Can Help Us Understand the Effects …
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controlled environmental chambers, transparent field enclosures, or open-top chambers. The fertilization factors averaged across the C 3 crops (rice, wheat, and soybeans)
are 24% for yield.
Assessing the Effect of Extreme Events
According to the Fifth Assessment Report of the Intergovernmental Panel on Climate
Change (IPCC), extreme weather events such as droughts, heat or cold waves, and
heavy rainfall leading to floods have increased since 1950. In this sense, variables
that measure extreme weather events are of interest to include in the econometric
models.
El Niño and La Niña are opposite phases that occur when the interaction between
the Pacific Ocean and the atmosphere above it changes from their neutral state in a
cycle known as the El Niño-Southern Oscillation (ENSO). El Niño and La Niña events
in the Pacific Ocean can be identified through the Southern Oscillation Index (SOI).
The SOI, obtained from the Australian Bureau of Meteorology (BOM), is calculated
using the pressure differences between Tahiti and Darwin. Sustained negatives values
of SOI below −7 indicate El Niño episodes, while sustained positives values of SOI
above +7 indicate La Niña episodes.
For the Argentine case, Ahumada and Cornejo (2019) found that an extreme event
associated with La Niña episodes (droughts) decreases soybean yields between 1 and
2% during 1973–2015. However, no significant effects were found for El Niño events.
Tack and Ubilava (2013) estimate the impact of both El Niño and La Niña on
average corn yields using a US county-level panel spanning 55 years (1950–2005).
They estimate the impact of El Niño (La Niña) on mean corn yields as the percentage
change in the mean of the El Niño (La Niña) regime relative to the mean of the neutral
regime. The county-level impacts range from −24 to 33% for El Niño and from −25
to 36% for La Niña. The negative effect of El Niño is found for the corn belt region,
and, as a result, the impact turns positive as one migrates both to the East and West.
The effects of El Niño and La Niña on crop yields may be accentuated if global
warming leads to an increase in the frequency and intensity of this type of events.
As Nordhaus and Reinhard (2016) warn, extreme weather events are expected to
increase worldwide and, given the local nature of some climate variables (particularly
precipitations), the effects can also be measured at a local level. Using an unbalanced
panel of 334 farms from 2002 to 2013, they analyze extreme weather events in the
case of winter wheat throughout the Netherlands. They found that high-temperature
events and precipitation events significantly decrease yields.
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controlled environmental chambers, transparent field enclosures, or open-top chambers. The fertilization factors averaged across the C 3 crops (rice, wheat, and soybeans)
are 24% for yield.
Assessing the Effect of Extreme Events
According to the Fifth Assessment Report of the Intergovernmental Panel on Climate
Change (IPCC), extreme weather events such as droughts, heat or cold waves, and
heavy rainfall leading to floods have increased since 1950. In this sense, variables
that measure extreme weather events are of interest to include in the econometric
models.
El Niño and La Niña are opposite phases that occur when the interaction between
the Pacific Ocean and the atmosphere above it changes from their neutral state in a
cycle known as the El Niño-Southern Oscillation (ENSO). El Niño and La Niña events
in the Pacific Ocean can be identified through the Southern Oscillation Index (SOI).
The SOI, obtained from the Australian Bureau of Meteorology (BOM), is calculated
using the pressure differences between Tahiti and Darwin. Sustained negatives values
of SOI below −7 indicate El Niño episodes, while sustained positives values of SOI
above +7 indicate La Niña episodes.
For the Argentine case, Ahumada and Cornejo (2019) found that an extreme event
associated with La Niña episodes (droughts) decreases soybean yields between 1 and
2% during 1973–2015. However, no significant effects were found for El Niño events.
Tack and Ubilava (2013) estimate the impact of both El Niño and La Niña on
average corn yields using a US county-level panel spanning 55 years (1950–2005).
They estimate the impact of El Niño (La Niña) on mean corn yields as the percentage
change in the mean of the El Niño (La Niña) regime relative to the mean of the neutral
regime. The county-level impacts range from −24 to 33% for El Niño and from −25
to 36% for La Niña. The negative effect of El Niño is found for the corn belt region,
and, as a result, the impact turns positive as one migrates both to the East and West.
The effects of El Niño and La Niña on crop yields may be accentuated if global
warming leads to an increase in the frequency and intensity of this type of events.
As Nordhaus and Reinhard (2016) warn, extreme weather events are expected to
increase worldwide and, given the local nature of some climate variables (particularly
precipitations), the effects can also be measured at a local level. Using an unbalanced
panel of 334 farms from 2002 to 2013, they analyze extreme weather events in the
case of winter wheat throughout the Netherlands. They found that high-temperature
events and precipitation events significantly decrease yields.