This week’s climate science
CIAT International Centre for Tropical Agriculture
This week sees the online launch of a new journal from the
Nature Publishing Group, Nature Climate
Change, paving the way for its paper launch in April 2011. The
journal will be publishing weekly articles online. This week's
offerings include "research highlights" focusing on the
positive effects of climate mitigation on the water cycle and
the likely
increase in hay-fever resulting from climate change.
African maize crops affected by heat
exposure
The main research article presented by Nature Climate Change is:
"
Nonlinear heat effects on African maize as evidenced by historical
yield trials". The study investigated the effect of daily
temperature on maize yields in Africa, comparing how yields were
affected under droughts and rain-fed conditions. The researchers
took a new approach, using records of the daily weather for
historical crop trials. Maize crop yield was found to be adversely
affected by the number of days the crops experienced high
temperatures. For every day spent at above 30°C, maize yield was
reduced by 1% in rain-fed trials, and by 1.7% in drought trials.
This research is important because maize had been assumed to be
relatively heat-tolerant.
Both the
Daily Mail and London freesheet
Metro ran nice articles summarising the findings of this
study.
Lobell, D.B., Bänziger, M., Magorokosho, C. & Vivek, B.
(2011) Nonlinear heat effects on African maize as evidenced by
historical yield trials. Nature Climate Change. DOI:
10.1038/nclimate1043
Ocean acidification
This month's Nature Journal features a thorough report about
ocean acidification, and its impact on organisms that grow calcium
carbonate shells: "Environment:
The Earth's Acid Test". The article highlights research showing
that different organisms respond variously to different levels of
ocean acidification, and to the combination of acidification with
other environmental stresses. The article considers the need for a
better understanding of the effects of ocean acidification, and the
urgency of this research.
Arctic ozone depletion
A joint
press-release from a group of international scientists has
detailed record levels of ozone loss from the Arctic ozone layer
over the last few weeks. The ozone loss is thought to result from
stratospheric cooling. This happens when greenhouse gases trap heat
energy in the troposphere, which is lower in the atmosphere than
the ozone layer. This prevents heat from passing to the
stratosphere causing cooling, which contributes to ozone loss.
Research to understand the interactions between ozone and climate
change is ongoing.
Does the Earth's core contribute to
warming?
An interesting paper published in the
Journal of Climate in January is still attracting attention
online. The study modelled the effect on surface air
temperature of small variations in day length resulting from the
flow of iron in the earth's outer core. It seems that the model
fits the observed surface air temperature data quite well, once the
effects of human-related climate change are removed.
Dickey, J.O., Marcus, S.L. & de Viron, O. (2011) Air
Temperature and Anthropogenic Forcing: Insights from the Solid
Earth. J. Climate, 24, 569-574. DOI:
10.1175/2010JCLI3500.1
Climate-related disasters can provide
opportunities
A study published in journal PNAS (Proceedings of the National
Academy of Science) finds that disasters relating to climate change
can provide opportunities for the poor: "
Climate-related disaster opens a window of opportunity for rural
poor in northeastern Honduras". The researchers found that
disasters can enable social and economic improvement, and enable
inhabitants to better cope with future disasters. This is
encouraging, and is in contrast to previous research which suggests
that the rural poor are particularly vulnerable in climate
disasters due to their reliance on natural resources.
McSweeney, K. & Coomes, O.T. (2010) Climate-related disaster
opens a window of opportunity for rural poor in northeastern
Honduras. PNAS. DOI:10.1073/pnas.1014123108