How tequila could be key in our battle against climate change

Now scientists are hoping to harness this reverse molecular clock to engineer new drought-resistant crops that will be able to adapt to our future changing climate.

Publishing their findings in this month's Nature Plants, the team from Newcastle University, UK, and Oak Ridge National Laboratory, Tennessee, reveal for the first time how the stomata -- or 'breathing' pores -- on the Agave's leaves are kept shut during the day to minimise water loss.

The process is opposite to that of most plants which keep their stomata open during the day so they can take in Carbon Dioxide and use the sunlight for photosynthesis. However, this also means they lose water rapidly through evaporation.

Newcastle University's Professor Anne Borland, one of the authors of the study, explains:

"Photosynthesis needs three key ingredients -- CO2, water and sunlight -- so it follows that most plants keep their stomata open in the day when it is sunny and shut at night when it is dark.

"But for a plant living in hot, arid conditions such as the Agave, this would be disastrous. They need to conserve every drop of water they can and leaving their stomata open during the day would result in such rapid water loss they would simply die.

"What we have shown in this study is that in so-called CAM plants -- Crassulacean Acid Metabolism plants like the Agave -- several of the genes controlling stomatal opening have had their abundance re-scheduled or 'flipped' from being more abundant during the day to more abundant at night.

"Storing the carbon from the CO2 taken up overnight, the plants photosynthesise in the day like other plants but are able to carry out the process without opening their stomata.

"If we can harness these genes and engineer new drought-resistant plants then the potential is huge in terms of developing crops and biofuels that are able to withstand the challenges we face from a changing climate."

CAM plants

Crassulacean acid metabolism (CAM) was first discovered by scientists at Newcastle University in the 1950s and is a photosynthetic adaptation found in approximately 7% of plant species.

Producing high quantities of starch and sugars in areas where water is limiting, it has long been recognised that if we can harness the properties of CAM plants they could pave the way to new biofuel crops for the production of bioethanol.

Agave is native to the hot and arid regions of Mexico and the Southwestern United States. Well-known as the base ingredient for tequila, Agave nectar is now widely marketed as an alternative to sugar.

Sequencing thousands of genes and proteins to understand the underlying metabolic processes, the team compared the Agave -- or CAM -- plant with Arabidopsis, a type of cress and a typical C3 plant.

They found that although both plants have the same complement of genes and proteins, over a 24 hour period certain genes were 'switched on' at different times.

"The plants have effectively re-programmed themselves to suit their environment," explains Professor Borland, based in the School of Biology at Newcastle University.

"Because both plant types have a similar genetic makeup, we are hopeful that it will be possible to turn C3 plants into CAM plants simply by finding the right triggers.

"This is a really exciting discovery and a major breakthrough in our quest to create new plants that can cope in our future environment."

The study is part of a $14m research programme funded by the Department of Energy Office of Science Genomic Science Programme. The team are currently four years into the five year project.

Climate change affects Swedish reindeer herding and increases tularemia infection

Warmer winters affect reindeer herding

In some places in the north of Sweden, the snow season has been shortened by more than two months between 1978 and 2008, which has dire consequences on life in the North. Data from ten weather stations in reindeer herding areas, from Frösön in mid-Swedish Jämtland to the very north of Sweden, shows that the coldest days have dwindled the most during the period and that long periods of really cold weather are today much less common than previously.

"Our research shows that climate change in northern Sweden is more extensive than anticipated and that reindeer herding is very vulnerable," says Maria Furberg, doctoral student at the Department of Public Health and Clinical Medicine and the Department of Clinical Microbiology.

Climate change in northern Sweden, indicated by shorter periods of snow for instance, has had negative effects on reindeer herders' livelihood. Reindeer herders' ability to handle the consequences is weakened further by other circumstances that also affect reindeer herding, such as for instance increased competition from other businesses, continuously shrinking grazing lands, predator policies and poor financial conditions.

Tenfold increase in incidence of tularemia

In her dissertation, Maria Furberg shows that the Swedish national incidence of tularemia, also known as rabbit fever (read more below), has increased significantly both geographically and in number between 1984 and 2012. The cases also seem to be related to watercourses and lakes. A survey of 1,500 randomly selected inhabitants in the two northernmost counties of Sweden, Norrbotten and Västerbotten, completed in 2014, showed that just under three per cent showed signs of having had a tularemia infection. That corresponds to a 16 time increase in comparison to reported cases.

"The massive increase in numbers of reported tularemia cases is startling and the disease seems to be much more common than previously anticipated. This means that our health care needs to improve tularemia diagnostics so that all patients receive the correct treatment. Also, the reasons behind the increase in tularemia needs to be investigated further with continuous research," says Maria Furberg.

Tularemia is a zoonotic disease, which means that it is transmitted from animals to humans. In Sweden, the disease is often mosquito-borne. The symptoms of the disease are high temperature, ulceration, swelling of lymph nodes and sometimes even severe pneumonia.

6,000 years ago the Sahara Desert was tropical, so what happened?

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The Sahara desert was once a tropical jungle.

Credit: © taka / Fotolia

As little as 6,000 years ago, the vast Sahara Desert was covered in grassland that received plenty of rainfall, but shifts in the world's weather patterns abruptly transformed the vegetated region into some of the driest land on Earth. A Texas A&M university researcher is trying to uncover the clues responsible for this enormous climate transformation -- and the findings could lead to better rainfall predictions worldwide.

Robert Korty, associate professor in the Department of Atmospheric Sciences, along with colleague William Boos of Yale University, have had their work published in the current issue of Nature Geoscience.

The two researchers have looked into precipitation patterns of the Holocene era nd compared them with present-day movements of the intertropical convergence zone, a large region of intense tropical rainfall. Using computer models and other data, the researchers found links to rainfall patterns thousands of years ago.

"The framework we developed helps us understand why the heaviest tropical rain belts set up where they do," Korty explains.

"Tropical rain belts are tied to what happens elsewhere in the world through the Hadley circulation, but it won't predict changes elsewhere directly, as the chain of events is very complex. But it is a step toward that goal."

The Hadley circulation is a tropical atmospheric circulation that rises near the equator. It is linked to the subtropical trade winds, tropical rainbelts, and affects the position of severe storms, hurricanes, and the jet stream. Where it descends in the subtropics, it can create desert-like conditions. The majority of Earth's arid regions are located in areas beneath the descending parts of the Hadley circulation.

"We know that 6,000 years ago, what is now the Sahara Desert was a rainy place," Korty adds.

"It has been something of a mystery to understand how the tropical rain belt moved so far north of the equator. Our findings show that that large migrations in rainfall can occur in one part of the globe even while the belt doesn't move much elsewhere.

"This framework may also be useful in predicting the details of how tropical rain bands tend to shift during modern-day El Niño and La Niña events (the cooling or warming of waters in the central Pacific Ocean which tend to influence weather patterns around the world)."

The findings could lead to better ways to predict future rainfall patterns in parts of the world, Korty believes.

"One of the implications of this is that we can deduce how the position of the rainfall will change in response to individual forces," he says. "We were able to conclude that the variations in Earth's orbit that shifted rainfall north in Africa 6,000 years ago were by themselves insufficient to sustain the amount of rain that geologic evidence shows fell over what is now the Sahara Desert. Feedbacks between the shifts in rain and the vegetation that could exist with it are needed to get heavy rains into the Sahara.

Warming up to weird weather As Chicago finally heats up, some experts point to altered jet stream and effects of climate change

Chicago started the year in the midst of a record stretch of 335 days without an inch or more of snow. Then we had the wettest April on record. Cold and wet weather in spring and early summer flooded homes, postponed baseball games and disrupted concerts and barbecues. July brought warm and dry weather, with exceptions — particularly one day late in the month when we exchanged T-shirts for sweatshirts. Then August started cooler than normal, with a hint last week of autumn.
"Worst. Summer. Ever," Shtulman wrote early this month in an email.
And maybe the weirdest too? What's going on here?
Weather experts say a warming planet has led to changed atmospheric circulation patterns in the jet stream, the fast-moving river of air that separates cold air from warm air and dictates weather patterns across the globe. They say the features within the jet stream that bring clouds and precipitation or dryness and extreme temperatures — low-pressure troughs and high-pressure ridges — are changing their movement and duration, creating unusual weather patterns that lock in place and cause major floods, cold spells and heat waves.
Consider McGrath, Alaska.
The town in May set 10 temperature records — six for daily lows around the middle of the month and four for daily highs near the end of the month, reported Anchorage television station KTVA.
Then, on June 17, McGrath hit an all-time record of 94 degrees.
Now consider Chicago.

Isolated Severe Storms Possible in the South Tuesday (FORECAST)

Strong to severe thunderstorms may rumble through parts of the Southeast during the first half of Tuesday.
Warm, unstable air will not be abundant for a widespread threat of severe storms, so we do not expect an outbreak. But, we could still see some damaging wind gusts and possibly a tornado on Tuesday. The thunderstorms are developing ahead of a surface low-pressure system that is tracking northeastward through the South to start this week.

Severe Weather Forecast
Tuesday

• Forecast: Thunderstorms will be ongoing during the morning in parts of the Southeast. The greatest chance of a few severe storms through the first half of the day will be from northern Florida to southern Georgia and coastal South Carolina. The potential for severe storms may taper off during the second half of the day.
• Threats: Damaging winds are the main threat, though a tornado is also possible.