Saturday, March 13, 2010

Global Warming Effects on Agriculture

Climate is the most significant factor in determining plant growth and productivity. Climate change is any long-term significant change in the average weather that a given region experiences. Average weather may include average temperature, precipitation and wind patterns.Without intervention to reduce emissions of greenhouse gases, global average surface temperature is projected to increase by about 0.2°C per decade during the 21st century. This swift change in climate will have major implications for agriculture around the globe.

Moisture and water availability will be affected by a temperature increase, regardless of any change in rainfall. Higher temperatures increase the evaporation rate, thus reducing the level of moisture available for plant growth, although other climatic elements are involved. Warming of the earth's atmosphere will significantly affect the wheat and maize yields across the globe. Reduced moisture availability would only add to the existing problems of infertile soils, soil erosion and poor crop yields.
Although climate changes may have some adverse impacts on agricultural production around the world, the increase in atmospheric carbon dioxide concentrations could be beneficial. Plants grow as a result of photosynthesis - the mechanism whereby the plant converts carbon dioxide from the atmosphere into food. With higher levels of carbon dioxide stimulating the rate of photosynthesis, the growth rate and productivity of plants could be expected to increase. This would be beneficial for global food stocks. Most crops grown in cool, temperate regions respond positively to an increased concentration of carbon dioxide, including some of the current major food staples such as wheat, rice and soybean. Some studies have shown that growth rate in these crops may increase up to 50% if carbon dioxide in the atmosphere is doubled. Crops grown in the tropical regions of the world, including sorghum, maize, sugar cane and millet, which combined, account for about one fifth of the world's food production, do not respond as well to increases in carbon dioxide.

In order to maintain agricultural output to meet the demand for a growing world population, farmers will have to adjust and adapt to compensate for a changing climate. Higher temperatures would increase the demand for irrigation of agricultural land. Unfortunately, in many arid and semi-arid regions of the world the demand for water already exceeds supply. Increased spread of pests and disease may also place additional demands on the need for fertilizers, pesticides and herbicides which are costly and unhealthy. The ability to adapt to the effects of climate change will vary greatly between regions. Economic and technological constraints will limit the rate of adaptability, with poorer economies lagging behind. Without planning and intervention, climate change will likely widen the gap between the rich and deprived areas of the world.

US & Canada are the major part of the problem

Here are some of the facts:
· The US consumes 20 million barrels of oil each day.
· The US has 5% of the world population, but contributes over 20% of greenhouse gas emissions.
· The US Has 30% of the world's automobiles.
· Canada has more registered cars than people.

When you put some of these figures together it is not hard to see that Canada and the United States are the major problem and source of global warming issues in the world. However, it goes much deeper then that. A few days ago as I was discussing to one of my friends about the global issues we face today, he said, "It is going to be a different world in 50 years" and I replied, "it will be a different world with or with out these issues". However it got me thinking about what it was like 50 years ago and how we got into this global warming and environmental mess today.

We have created a culture of perceived wants and have made them into needs. When I was growing up in Canada, as a child we didn't have cell phones, cameras, ipods, computers, and we didn't have televisions in every room. In fact, if we had one television in the house we were fortunate. Times have certainly changed. I found that a lot of parents from the 1980s and beyond period grew up with the attitude I am going to give my kids everything I have never had. Everything means material items! Now as a result, kids now believe that a cell phone is now a need, a computer and television in the bedroom is now a need, and all the latest technology gadgets are a need as well. I can also remember a time when a family would have 3 or more kids and it was not unlikely for them to be sharing a bedroom with their brother or sister, well we don't do that anymore. So now we build bigger houses with more bedrooms. Now when kids turn 16 they all want a car because their friends have one. The list goes on and on, and you know exactly what I am talking about if you are a parent. We have peer pressure to encourage our children to have everything they want. Furthermore, the media on televisions, the internet and billboards bombard us with the message to consume, consume, and consume more.

We have spoiled our youth to the point that they now believe it is their god given right to have all the toys and wonderful things life has to offer. I often hear them saying that we deserve this or that. I have huge issues with that type of attitude when over a billion people in other parts of the world are starving and don't have adequate drinking water. We have created a culture of greed and have redefined it as what we want and made it a "perceived need". The United States and Canada are consuming more then any other country on the planet, and our hunger for consumer items is forever increasing. In essence we have a generation of spoiled materialistic people running these rich nations, and we are going to destroy ourselves with greed.

I live in Canada and I have to admit we are a major part of the problem. Here in North America we are the major producers of CO2 emissions, and contribute to creating more global warming issues then any other country on the plant. We are creating a culture of consumption and waste and have a huge appetite for fuel, oil and the luxuries of life. Each generation seems to want more and more. We seem to have lost our way in a materialistic society. We need to change our way of life if we want to solve the global warming and climate change issues.

Global Warming and the Artic Ice Melt

The Arctic is the measuring stick for global warming. The Artic is an extremely sensitive region, and it's being greatly affected by the changing climate. Most scientists view what's happening now in the Arctic as a hint of things to come. Average temperatures in the Arctic region are rising twice as fast as they are elsewhere in the world. Arctic ice is getting thinner, melting and rupturing. For example, the largest single block of ice in the Arctic, the Ward Hunt Ice Shelf, had been around for 3,000 years before it started cracking in 2000. Within two years it had split all the way through and is now splitting into pieces. The Arctic is warming at double the rate of the rest of the world and ice shrank to a record low in 2007, leading to concerns that it could pass a point of no return. Less than three decades ago, there would still be seven million square kilometers or 2.5 million square miles of ice left at the end of an Arctic summer. That's now dropped by almost forty percent.

Drastic changes are occurring in the Artic region, affecting the ice both in the open ocean and the ice, which is attached to the coast. Many scientists believe that the Artic will have ice-free summers in 2013, which is earlier than previously predicted. The Artic is experiencing vast ice melts from the retreat of the glaciers, to the melting of the sea. The fate of the massive ice blocks is viewed as a key indicator of global warming and climate change. When ice shelves break apart, they drift offshore into the ocean as "ice islands", transforming the geography of coastlines. Temperatures in the artic region have risen noticeably during the past few decades. The Arctic climate varies naturally, but the researchers confirmed that human-influenced global warming is partially responsible. They warn the shrinkage could lead to even faster melting in coming years. The melting may also contribute to even higher arctic temperatures in the future. Some scientists are concerned that melting Arctic sea ice will dump enough freshwater into the North Atlantic to interfere with sea currents. They believe that the thawing of sea ice covering the Arctic could disturb or even halt large currents in the Atlantic Ocean, which are responsible for warmer airflows. Retreating ice cover exposes more of the ocean surface, allowing more moisture to evaporate into the atmosphere and leading to more precipitation. Ice cover loss can influence winds and precipitation on other continents, possibly leading to less rain in the western United States.. This could actually result in lower temperatures for some areas, particularly Europe and the eastern part of North America. There would be more rain and snow in these regions. More violent storms are also more likely as a result of the melting artic ice.

The contraction of the Arctic ice cap is accelerating global warming. Snow and ice usually form a protective, cooling layer over the Arctic. When that covering melts, the earth absorbs more sunlight and gets hotter. And the latest scientific data confirm the far-reaching effects of rising global temperatures. Melting glaciers and land-based ice sheets also contribute to rising sea levels, threatening low-lying areas around the globe with beach erosion, coastal flooding, and contamination of freshwater supplies. A warmer Arctic will also affect weather patterns and thus food production around the world. Arctic ice helps regulate and temper the climate in many areas around the world. The less ice there is, the more dramatic the impact on global weather patterns. Huge sheets of ice reflect solar radiation, keeping our planet cool. When that ice melts, huge expanses of darker, open ocean water absorb the heat instead, warming things up. Although few humans live in the Arctic, the disappearance of this ice cover can have effects far beyond the few residents and the wildlife of this harsh region.

The melting of once-permanent ice is affecting native people, wildlife and plants. Polar bears, whales, walrus and seals are changing their feeding and migration patterns, making it harder for native people to hunt them. And along Arctic coastlines, entire villages will be uprooted because they're in danger of being swamped. The native people of the Arctic view global warming as a threat to their cultural identity and their very survival.

Environmentalists have pointed out the state of the polar bear as a symbol of global warming caused by human activity. The Arctic sea ice melt is a disaster for the polar bears. They are dependent on the Arctic sea ice for all of their essential behaviors, and as the ice melts and global warming transforms the Arctic, polar bears are starving, drowning, even resorting to cannibalism because they don't have access to their usual food sources. Polar bears depend on sea ice as a platform for hunting seals and as a pathway to take them to coastal areas. The ice shrinkage has forced polar bears to cover longer distances between ice and land United States government scientists predict that two-thirds of the world's polar bears will be killed off by 2050 and the entire population gone from Alaska because of thinning sea ice from global warming in the Arctic. The worldwide population of polar bears currently stands between 20,000 and 25,000, broken into groups in Russia, Denmark, Norway, Canada and US state of Alaska. One-quarter to one- fifth of that population occupies waters off the shores off Alaska or the nearby coastlines, with separate groups in the Chukchi Sea off northwestern Alaska, the Northern Beaufort Sea and the Southern Beaufort Sea off the North Slope of Alaska. The most-studied bear population, in the Western Hudson Bay in Canada, dropped over twenty percent from 1987 to 2004, stated the Canadian Fish and Wildlife Service.

When we burn fossil fuels like oil, coal and gas to generate electricity and power our vehicles, we produce the heat-trapping gases that cause global warming. The more we burn, the faster churns the engine of global climate change. Thus the most important thing we can do is save energy. Many experts on the Arctic say that global warming is causing the ice to melt and that the warming is at least partly the result of the buildup in the atmosphere of heat-trapping gases emitted from automobile exhausts and industrial smokestacks.

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