There is no question that global warming is occurring. The squabbling centers more on the cause and if major corrective actions are necessary.

From records collected starting in 1880, there is specific data showing that a warming of the planet proceeded until 1940 and then a global cooling occurred until about 1972 when another warming trend began and continues today, explained Elwynn Taylor, Ph.D., Iowa State University climatologist and agricultural consultant on weather trends.

The warming and cooling occurs along trend lines similar to the yield trend lines for crops. Not every year's global temperature reading is exactly on the trend line but can be above or below the overall trend, as shown by Taylor during the annual meeting of the American Society of Farm Managers and Rural Appraisers.

Taylor said for decades it has been taught in college that the planet has been warming since 20,000 years ago when the glaciers began melting. He then noted that the glaciers are still melting, and our planet is still warming. Of course, the short three decade minor cooling really concerned people at the time and no one discovered a reason, he said.

"My first professor in graduate school said the climate is changing. The climate has always changed. The questions in 1966 were how much will the climate change, how fast will the climate change and why is the climate changing. And those are still the questions," Taylor said.

How weather and global warming interact is not as straightforwardly possible to explain as most people would like. "There are a lot of things we don't have the knowledge about yet. So, looking at the theories or what the theoretical physicists are coming up with is about all we have to go on," Taylor said.

Evidence Noted

It isn't all theory to the world’s leading multinational companies with agricultural divisions. "There is evidence of the impact of climate change all over the world. In the U.S. it is very well documented," said Nick Hamon, vice-president and head of sustainability for Bayer CropScience North America. "Insects are turning up in places where we haven’t seen them before, certain weed species are moving farther north than previously observed, and the plant hardiness zone maps have been adjusted. Not all these changes can necessarily be attributed to climate change, some may be related to urbanization and mobility of the population."

Taylor didn't address pests and diseases, but he did reference rainfall as an example of a weather change. He noted the gradual increase in precipitation in the Midwest since the 1950s. The term "100-year flood" was calculated in the 1950s, but with more precipitation, what was called a "100-year flood" now translates into a 17-year extreme flood cycle, six times more often.

"If the planet becomes five degrees warmer, the water coming from the Gulf of Mexico, which is where the precipitation from the Midwest comes from, flooding will increase even more. That water in the Gulf of Mexico will evaporate into the warmer air, which can hold more water than cooler air, and it will carry that water up to the Plains, and it will rain 14 percent more," Taylor said.

In that scenario, more plants will grow, but the runoff will still increase, and floods every 12 years will be equivalent to the original 100-year floods.     

Company Reactions

With the fact of global warming and theories of the potential effects on agriculture, the multinational agricultural companies are preparing for continued change. "I don't think any company the size of Bayer can ignore the whole idea of climate change and the impact it might have on our business and that of agriculture 10 or 20 years down the road. New product lead times of 10 to 15 years are not uncommon. This means we really have to be tuned in and looking closely at trends over the next 50 years," said Hamon, who has been a manager for innovation in ag chemicals and environmental sciences dating back to the 1980s.

Hamon's explanations of what companies are doing and Bayer's planning process for the future is in line with what the other five largest multinational agribusinesses' management is expressing to the media and to their employees. Bayer appears to be a leader in climate change mitigation with its own Web site at, which includes extensive linking of future weather impact and sustainability programs.

A look at the future has to consider sustainability, Hamon explained. "It is not just about climate change. It is about climate, water, urbanization and population growth. They are four of the biggest drivers, and they are all interlinked." Sustainability is a commitment to living and conducting business in a way that meets the needs of the present without compromising the ability of future generations to meet their own needs.

Hamon said that research-based manufacturers such as Bayer are focusing on technology to help lead us into the second green revolution that will be needed to feed a projected world population of 9.2 billion people by 2050, without destroying the environment. This means increasing crop yields while reducing the resources needed to grow more food, feed, fiber and fuels on less land.

Research into biotic (insects, weeds disease) crop stress management is important, but there is increasing focus on abiotic stress management (drought and heat tolerance, salinity, nutrient utilization and soil quality) at Bayer.

"The climate change models indicate that some parts of the world could see some agricultural benefits from global warming," Hamon said. "When it comes to growing wheat in central to northern Russia, a few degrees hugher temperatures and a longer growing season could have a huge impact on wheat yields. But the predictive models of what could happen in Africa, for example, are very, very devastating because of drought, coupled with population growth. Predictive models also show major water shortages worldwide, including North America." 

Carbon Sequestration

"Carbon sequestration (carbon accumulation in plants and soils) is possibly the most powerful tool we have to manage carbon dioxide levels in the atmosphere, and that is all about growing healthy plants. Bayer knows about how to grow healthy plants and at the same time increase yields. It is our core competency as a leader in crop protection. So, there is both a sense of responsibility as well as business opportunity," Hamon said.  Every one of us has a carbon footprint, and industry is a major contributor of greenhouse gasses. That is why Bayer has spent $1.5 billion over the past three years to reduce the footprint of its business as well as focus its research and development activities on technologies that can help tackle global issues such as climate change.

European-based companies are already living with the idea of carbon taxes and cap and trade requirements, whereas in the U.S., reducing greenhouse gas emissions is still voluntary.

"Manufacturing creates carbon emissions, and companies can have a major impact by improving the efficiency of their processes, reducing their overall footprint but also saving money at the same time. It is good business sense to reduce your carbon footprint, as well as good for the planet," Hamon said.

2025 Disease Year?

"They (companies) need to adjust to what the climate is doing whether it is people causing it or not," said Taylor. "I don't think we need companies adjusting to what the climate is going to be in 100 years; we need them adjusting to what the climate is going to be in 20 years. And I think we know the outlook pretty well without worrying about manmade climate change. We are going through a warming trend; there is no question about it. If it is a trend that peaks in 2025 and it starts cooling, then companies can adjust again.

"I didn't pull that 2025 out of a hat," Taylor went on to say. "The harshest year in the past century was 1936. The harshest year of the previous century, the 1800s, was 1847 — so, we have 1847, 1936 and 2025. And we've seen this same pattern for 800 years from tree growth rings."

The cycle is every 89 to 90 years to have a rough year in agriculture. Taylor concluded by saying, "If we are going to have Dust Bowl-like conditions this century, then it will probably be close to 2025. So, it is something that companies need to be preparing for whether there is human global warming impact or not."