What does climate change mean and what causes it?
Global warming and climate change are terms for the observed century-scale rise in the average temperature of the Earth's climate system and its related effects which both are a widely discussed and debated area. Anticipated effects include warming global temperature, rising sea levels, changing precipitation, and expansion of deserts in the subtropics. The likely changes include more frequent extreme weather events including heat waves, droughts, heavy rainfall, and heavy snowfall, ocean acidification: and species extinctions due to shifting temperature regimes. Effects significant to humans include the threat to food security from decreasing crop yields and the abandonment of populated areas due to flooding. The greenhouse effect is a process by which thermal radiation from a planetary surface is absorbed by atmospheric greenhouse gases, and is re-radiated in all directions. Since part of this re-radiation is back towards the surface and the lower atmosphere it results in an elevation of the average surface temperature above what it would be in the absence of the gases. Human activity, primarily the burning of fossil fuels and clearing of forests, have intensified the natural greenhouse effect, causing global warming – and has increased the amount of greenhouse gases in the atmosphere, leading to increased radiative forcing from CO2, methane, tropospheric ozone, CFCs and nitrous oxide.
Within the past 135 years, nine of the 10 warmest years in the instrumental record occurred since 2000, with 2014 being the warmest year on record. 2014 was also the 38th consecutive year with above-average temperatures.
In its 2014 report the Intergovernmental Panel on Climate Change (IPCC) reported that scientists were more than 95% certain that most of global warming is caused by increasing concentrations of greenhouse gases and other human activities. The global warming is happening faster than anticipated within the past 1300 years. Globally, the fossil fuel burning has produced about three-quarters of the increase in CO2 from human activity over the past 20 years. The rest of this increase is caused mostly by changes in land-use, particularly deforestation (IPPC summary report 2001).
What are the impacts of global warming?
IPCCs report (2007) states that during the last 100 years and up to the 2000s the most significant impacts from the global warming are:
Conventional agriculture and the climate change
Relying solely on the chemical inputs in agricultural production leads to many negative effects on our climate such as the reduction of natural carbon sinks (carbon stored for instance in plants). Natural carbon sinks are forests, soils, oceans, or other natural environment viewed in terms of its ability to absorb more carbon dioxide from the atmosphere than it releases.
The main carbon sinks are the oceans with an estimated absorption of about one third of the carbon dioxide emissions caused by human activity. Efficient carbon sinks are also plants that store carbon through photosynthesis – a process used by plants and other organisms to convert light energy, normally from the Sun, into chemical energy that can be later released to fuel the organisms' activities. At best, carbon can be sequestered up to hundreds of years out of the atmosphere. However, when circumstances change, these sinks can turn into carbon sources, releasing more carbon dioxide into the atmosphere than they can absorb. Many of the conventional agricultural practices lead to carbon loss from soils, warming oceans are less able to store organic carbon and deforestation, i.e. when forests are cut down, not only does carbon absorption cease, but also the carbon stored in the trees is released into the atmosphere as CO2.
Climate change and the future
Global warming is expected to be greatest in the Arctic, with the continuing retreat of glaciers, permafrost and sea ice. Mountain glaciers and snow cover have declined on average in both hemispheres and for instance in the Andes Mountains an annual retreat is an average of 33 meters (108 ft). Widespread decreases in glaciers and ice caps have contributed to the sea level rise (IPPC 2007 report). In the past 100 years, many of the mountain glaciers in the tropical areas have lost about 80% of their masses. In 1988, according to NASA, the glaciers in Greenland melted by one meter in a year.
Even if we are able to stop all of the CO2 emissions today, the past carbon dioxide emissions will have a long lasting effect – up to a minimum of hundreds of years in the atmosphere. If the human society continues in the business as usual, IPPC’s 2014 report states that the average temperature may rise up to 4.8 °C (8.6 °F). Some estimations state that during the summer months the arctic areas may become iceless after just a few more years.
”Greenland lost 150– 250 cubic kilometers of ice in between 2000-2006.”
Consequently, the reduction of global CO2 emissions only slows down the climate change but it will not stop it. Instead, by radically increasing carbon sequestration in the global agriculture, one would have a significant effect on reducing and even reversing the climate change.
Challenge of the North – Eutrophication of the Baltic Sea
Eutrophication is the biggest problem of the Baltic Sea and it is caused by nitrogen and phosphorus emissions, which nourish the growth of algae in the water. Baltic Sea is located in between countries such as Finland, Sweden, Denmark, Estonia and Russia. There are recurrent oxygenless periods in the deep basins of the Baltic Sea. Due to the slow water turnover, environmental toxins and eutrophying nutrients remain in the Baltic Sea and cause long-term effects. There has been an increase in the visible symptoms of eutrophication, such as blue-green algae. Nitrogen and phosphorus drift into the sea in wastewater from cities and along with rainwater from fields.
The CO2 emissions originating from farms can be influenced via use of renewable energy sources, taking good care of the soil in fields and by increasing the carbon sinks. Increasing the amount of nitrogen rich plants as part of crop rotation results in the reduction of use of chemical fertilizers and also reduces the carbon dioxide emissions. Nitrogen rich plants enable farmers to produce environmentally friendly food, feed and fertilizers, at best without use of any ammonium forming nitrogen fertilizers. The resulting manure from livestock production can be treated efficiently with the right storage and handling methods, in order to fuel the plant growth.
Agriculture emissions can be reduced for example by:
United Nations Commission on Trade and Development report (2013) and Rodale Institute’s report (2014) state that reversing climate change is possible via regenerative agriculture. These reports claim that one can sequester more than 100% of current annual CO2 emissions with a switch to widely available and inexpensive organic management practices.
In the following, the key differences in between conventional farming and regenerative farming are briefly presented.
By improving growth conditions of the soil we increase food security and minimize risks like crop failures. Higher carbon content enables the soil to make more water and nutrients available to support crop and plant growth. Soil carbon plays a role in maintaining the biotic habitants that make land management systems sustainable, resilient and able to resist degradation. Regenerative farming also improves water retention and plant uptake. These climate-friendly agricultural methods are low-cost in a long run and benefit especially small-scale farmers and farmworkers, who are the majority of hungry people.
The effects of climate change has created a new group of refugees: climate refugees. These people are being forced to move from their habitats because climate change related problems such as lack of food or extreme weather conditions. If we strengthen the global food security and succeed in reversing climate change the amount of climate refugees would decrease.
Quality of food
Our food will be healthier and more nutrient-rich therefor that the methods used in regenerative farming increase soil organic material and the amount of nutrients in the soil. Also, when we
minimize the use of artificial fertilizers, pesticides and herbicides the amount of chemicals in our food will decrease. These two together affect considerably to the quality of our food.
Farmers save money due to reduced use of synthetic petrochemical fertilizers and pesticides while emitting less C02.
For further information and research on regenerative farming, please refer to the following links.