News / Africa

Many Unknowns about Future Climate Change Effects

Many Unknowns about Future Climate Change Effects
Many Unknowns about Future Climate Change Effects
Joe DeCapua

Scientists say many of the long-term effects of rising temperatures are still unknown. They’re discussing the problem at the U.N. climate change conference in Durban, South Africa. Researchers say climate change is a complex mix of potential benefits and consequences, especially regarding food production.

In early November, researchers from several countries met in Beijing. They represented the so-called BRICS countries – Brazil, Russia, India, China and South Africa – as well as the United States and Indonesia. They discussed climate change and food security and agreed on a number of issues and recommendations to present to the Durban conference.

One of those researchers – Gerald Nelson – said they came up with a work program for climate change treaty negotiators. It concentrates on the role of agriculture.

“The advantage of the work program is that it puts these research findings about the importance of looking at climate change effects on agriculture – and also agriculture’s role in mitigation – directly into the record for delegates to look at,” he said.

We know we don’t know

Nelson is a senior fellow at IFPRI, the Washington-based International Food Policy Research Institute.

The ancient Greek philosopher Socrates is quoted as saying, “I know that I don’t know.” Nelson said it’s not that researchers don’t know anything about climate change, it’s just that they need to know a lot more.

"Our research results, our understanding of what’s going on on the surface of the planet today, is really hindered by a lack of data. We just have very little information about the actual changes that are taking place on the planet. We are still groping, perhaps not in the complete dark, but with only very limited illumination, to understand those changes. And we need to do a much better job of collecting data about where things are changing and how they’re changing,” he said.

Good and bad

At first glance, some of the changes being seen appear to be beneficial, at least for now.

“Take for example, in Iowa, farmers there are seeing longer growing seasons. They’re planting earlier in the year. They’re seeing wetter springs, with more summer precipitation happening. If you take a look at China, you see that Heilongjiang Province, which used to have essentially no rice production, now accounts for 15 percent of China’s rice production. In the northern parts of Russia, you’re finding grain growing that was not possible to grow there 20 or 30 years ago,” he said.

But what if global temperatures continue to rise? Would those apparent benefits continue? Maybe not.

“In the short run, they do seem to be positive,” said Nelson, “That is, rice production further north because it’s warmer potentially is a good thing for China. It’s harder to sort out the climate signals as you get towards the middle of the planet. It’s the northern extremes where you can see it earlier. But of course that’s with the climate change we have so far.”

Nelson says predictions call for substantially greater temperature increases. He says there’s been about a one degree Celsius rise over the past 100 years. But the forecast is for a two degree Celsius increase by 2050. Such an increase, he says, could have a dramatic effect on corn or maize.

“The corn plant, for example, can do ok as long as the temperature is in the range of 30 to 31 degrees Celsius. But as the temperature increases get above 30 or 31 to 32 or 33, recent research has shown substantial drop-off in yields,” he said.


Nelson and others at the Beijing meeting came up with a list of 12 climate change priorities. One of them warns that a rise in temperature can also mean a rise in pests that attack crops.

“For insects, in particular, as the temperatures rise then they reproduce more rapidly. So, instead of having three cycles of a pest per season you might end up with four or five. And that means more damage to the plants as they grow,” he said.

And as temperatures rise, regions may lose killing frosts, which help limit insect populations. As for weeds, many are thriving in the richer CO2 or carbon dioxide environment.

Then there are ruminants, animals that produce lots of methane gas while digesting their food. Nelson says methane is much more powerful than CO2. More nations are expected to raise livestock for food as their lifestyles improve.

Other priority areas include soil ecosystems, irrigation, land use, biotechnology, food supply storage losses and training for researchers, farmers and others to better deal with climate change.

You May Like

US, China Have Dueling Definitions of Cybersecurity

Analysts say attribution or or proving that a particular individual or government is responsible for a hack, is a daunting task More

Snowden: I'd Go to Prison to Return to US

Former NSA contractor says he has not received a formal plea-deal offer from US officials, who consider him to be a traitor More

Goodbye Pocahontas: Photos Reveal Today's Real Native Americans

Weary of stereotypes, photographer Matika Wilbur is determined to reshape the public's perception of her people More

This forum has been closed.
There are no comments in this forum. Be first and add one

Featured Videos

Your JavaScript is turned off or you have an old version of Adobe's Flash Player. Get the latest Flash player.
Russia’s Syria Involvement Raising Concerns in Europei
Luis Ramirez
October 02, 2015 4:45 PM
European nations are joining the United States in demanding that Russia stop targeting opposition groups other than the Islamic State militants as Russian warplanes continue to conduct raids in Syria. The demand came in a statement from Britain, France, Germany, Qatar, Saudi Arabia, Turkey and the United States Friday. VOA Europe correspondent Luis Ramirez reports.

Video Russia’s Syria Involvement Raising Concerns in Europe

European nations are joining the United States in demanding that Russia stop targeting opposition groups other than the Islamic State militants as Russian warplanes continue to conduct raids in Syria. The demand came in a statement from Britain, France, Germany, Qatar, Saudi Arabia, Turkey and the United States Friday. VOA Europe correspondent Luis Ramirez reports.

Video First Self-Driving Truck Debuts on European Highways

The first automated semi-trailer truck started its maiden voyage Friday, Oct. 2, on a European highway. The Daimler truck called 'Actros' is the first potentially mass-produced truck whose driver will be required only to monitor the situation, similar to the role of an airline captain while the plane is in autopilot mode. VOA’s George Putic reports.

Video Nano-tech Filter Cleans Dirty Water

Access to clean water is a problem for hundreds of millions of people around the world. Now, a scientist and chemical engineer in Tanzania (in East Africa) is working to change that by creating an innovative water filter that makes dirty water safe. VOA’s Deborah Block has the story.

Video Demand Rising for Organic Produce in Cambodia

In Cambodia, where rice has long been the main cash crop, farmers are being encouraged to turn to vegetables to satisfy the growing demand for locally produced organic farm products. Daniel de Carteret has more from Phnom Penh.

Video Migrant Influx Costs Europe, But Economy Could Benefit

The influx of hundreds of thousands of refugees and migrants is testing Europe’s ability to respond – especially in the poorer Balkan states. But some analysts argue that Europe will benefit by welcoming the huge numbers of young people – many of them well educated and willing to work. Henry Ridgwell reports from London.

Video Botanists Grow Furniture, with Pruning Shears

For something a bit out of the ordinary to furnish your home, why not consider wooden chairs, crafted by nature, with a little help from some British botanists with an eye for design. VOA’s Jessica Berman reports.

Video New Fabric Helps Fight Dust-Related Allergies

Many people around the world suffer from dust-related allergies, caused mainly by tiny mites that live in bed linen. Polish scientists report they have successfully tested a fabric that is impenetrable to the microscopic creatures. VOA’s George Putic has more.

Video Burkina Faso's Economy Deeply Affected by Political Turmoil

Political turmoil in Burkina Faso over the past year has taken a toll on the economy. The transitional government is reporting nearly $70 million in losses in the ten days that followed a short-lived coup by members of the presidential guard earlier this month. The crisis shut businesses and workers went on strike. With elections on the horizon, Emilie Iob reports on what a return to political stability can do for the country's economic recovery.

Video Fleeing Violence, Some Syrians Find Refuge in Irbil

As Syrians continue to flee their country’s unrest to seek new lives in safer places, VOA Persian Service reporter Shepol Abbassi visited Irbil, where a number Syrians have taken refuge. During the religious holidy of Eid al-Adha, the city largely shut down, as temperatures soared. Amy Katz narrates his report.

Video Nigeria’s Wecyclers Work for Reusable Future in Lagos

The streets and lagoons of Africa's largest city - Lagos, Nigeria - are often clogged with trash, almost none of which gets recycled. One company is trying to change that. Chris Stein reports for VOA from Lagos.

Video Sketch Artist Helps Catch Criminals, Gives a Face to Deceased

Police often face the problem of trying to find a crime suspect based on general descriptions that could fit hundreds of people in the vicinity of the crime. In these cases, an artist can use information from witnesses to sketch a likeness that police can show the public via newspapers and television. But, as VOA’s Greg Flakus reports from Houston, such sketches can also help bring back faces of the dead.

Video Thailand Set to Build China-like Internet Firewall

Thai authorities are planning to tighten control over the Internet, creating a single international access point so they can better monitor content. VOA Correspondent Steve Herman reports from Bangkok on what is being called Thailand’s own "Great Firewall."

Video Croatian Town’s War History Evokes Empathy for Migrants

As thousands of Afghanistan, Iraqi and Syrian migrants pass through Croatia, locals are reminded of their own experiences with war and refugees in the 1990s. VOA's Daniel Schearf reports from the town of Vukovar, where wartime scars still are visible today.

Video Long Drought Affecting California’s Sequoias

California is suffering under a historic four-year drought and scientists say even the state's famed sequoia trees are feeling the pain. The National Park Service has started detailed research to see how it can help the oldest living things on earth survive. VOA’s George Putic reports.

VOA Blogs