Global climate

Poor countries are generally more vulnerable to climate change than rich countries. They are more exposed to the negative consequences of climate change and have fewer resources to handle the impacts. We expect the long-term trend of a rise in total emissions of greenhouse gases to continue unless much more substantial measures are taken.

Mean temperatures increasing and sea levels rising

Significant changes have occurred in the climate over the past hundred years, this is especially true for the last 50 years. The decade 2000-2010 was warmer than the 1990s, which were warmer than the 1980s.

According to the National Oceanic and Atmospheric Administration (NOAA) 2014 was the warmest year on record, with a global annual temperature of 0,69 above average. Four out of five of the warmest years on record have occured during the 21st century, with 1998 as the exception. The global annual temperature has increased at an average rate of 0.06°C per decade since 1880 and at an average rate of 0.16°C per decade since 1970.

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The above graph shows that the mean temperature varies from year to year. Weather phenomena such as El Niño and La Niña and changes in the sun's radiation intensity are assumed to be considerable causes of these variations.

If we look at the development of the mean temperature over longer periods, we can draw more robust conclusions: The 2000s were warmer than the nineties, which in turn were warmer than the eighties. 

Global warming caused by human activity

In its Fifth Assessment Report the International Panel on Climate Change (IPCC) states that it is more than 95 percent certain that humans have caused more than half of the temperature increase since 1950. It is likely that the average temperature of the Northern Hemisphere has been higher in the past 30 years than in any other 30-year period during the last 1400 years.

The concentrations of the greenhouse gases CO2, methane and N2O have risen considerably as a result of human activity since 1750, and clearly exceed preindustrial values. This has increased the atmosphere’s greenhouse effect, and is considered to be the main cause of global warming. 

In its fifth report the IPCC has defined a set of four new scenarios, denoted Representative Concentration Pathways (RCPs). They are identified by their approximate total radiative forcing in the year 2100 relative to 1750. If we follow the lowest emission pathway, we may limit temperature increase to 2°C by the end of this century compared with the average temperature for the period 1850-1900. But if we do not limit our emissions, global temperature may surpass 4°C.

Serious consequences for the environment, health and economy

A change in the global climate may have serious environmental and socio-economic consequences.

Climate change may well occur faster than natural ecosystems can adapt. There will be a risk that a number of endangered species may become extinct. Regional temperature change and shifts in rainfall patterns will alter conditions for farming, potentially reducing food production and causing losses of income for farms. Extreme weather phenomena may become more frequent and more violent. Our health may also be affected as diseases such as malaria spread to new regions with the rising temperatures.

Loss of land areas and risk of floods

A rising sea level will submerge low-lying land and increase the risk of flooding. Many of the world’s most diverse and productive ecosystems lie near the coast, and in most countries the population centres, and economic centres, tend to be concentrated in the coastal zone.

Weather conditions more extreme

Natural disasters related to climate change are expected to increase in intensity and frequency in the years to come and may have considerable demographic consequences and result in social unrest.

Poor countries most vulnerable

Poor developing countries are generally more vulnerable than developed countries. This is because they are located in  regions more exposed to the negative effects of climate change, and because they have less resources to deal with the impacts of climate change.

Climate closely connected to socio-economic development

Global warming is one of those environmental issues that are most intimately linked to socio-economic development. This is true in poor and rich countries alike. Our impact on the environment depends on a range of factors: the world population, per capita consumption of energy and goods, the type of goods and services preferred by consumers, and how goods are produced, transported, and used.

More than 9 billion people in 2050

The world's population has more than doubled since 1950, and is forecasted to grow to more than 9 billion in 2050 before the growth flattens off. The growth spots are very unevenly distributed, with 95 per cent of expected growth in poor countries.

Economic growth means environmental impact

In rich countries consumption is growing steadily and fairly rapidly, despite low population growth. Basic needs such as food, clothing and shelter have long been met, and higher quality and more refined products are demanded. New needs are being created all the time. Fundamental changes in consumption patterns have occurred in rich countries as incomes and total consumption have risen. Some services, especially transport, are growing even faster than total consumption.

As the globalization of the world economy continues, world trade will grow and with it production and transport volumes. Economists argue that liberalization of trade means more efficient utilization of resources, which will expand the world's total production of goods and services, thus building a basis for better welfare throughout the global community.

But liberalization also means more transport, production and faster depletion of resources, heavier impacts on biodiversity, and added emissions of pollutants. If liberalization is to have a net positive effect on the state of the environment, there is no alternative but to adopt powerful environmental protection policies at the global and national level.

Greenhouse gas emissions on the rise

The gases that contribute to the greenhouse effect are primarily carbon dioxide (CO2), methane, N2O and HFCs. The concentration of these gases in the atmosphere is the highest registered in the last 800 000 years. According to the IPCC the concentrations will continue to rise. How much depends on, among other factors, developments in emissions.

The ongoing increase in green house gas emissions had only a short intermission in connection with the economic crisis in 2008 and 2009. The concentration of CO2 in the atmosphere also increases, but not with the same speed as the emissions. This is because about half of the anthropogenic emissions of CO2 are taken up by marine ecosystems and soil / vegetation.

Growth in regioanl CO2 emissions, 1990-2008

Global partnership required

A global environmental problem like climate change can only be mitigated by binding international cooperation.  Such cooperation is laid down by the UN Framework Convention on Climate Change. The long-term goal is that the concentration of greenhouse gases in the atmosphere should be stabilized at a level that prevents dangerous and negative anthropogenic interference with the climate system.

The Convention states that developed countries must take the lead in combating climate change and its adverse effects. Among other things, a climate fund to assist developing countries in their efforts to tackle the challenges of climate change has been established. The fund's assets are, however, currently quite limited.

The Kyoto Protocol

The Kyoto Protocol entered into force in 2005. A total of 192 countries and one regional economic organization (the EC) have ratified the agreement. During the first commitment period from 2008 to 2012 the developed countries' total emissions of the main greenhouse gases were to be reduced by five percent below 1990 levels. The emissions reduction obligations have varied from country to country. 

Fewer countries have taken on commitments to reduce emissions in the second period, from 2013 to 2020, than in the first period.

More fundamental measures needed

The instruments used to control greenhouse emissions reflect the natural complexity of the issue which affects all walks of life. Most of them focus on technical measures since this is the most realistic way to achieve results in the short and medium term.

A more lasting response to the solution of  the climate change issue, however, would probably demand more fundamental measures that will have far-reaching implications on how society is organised today.