Future scenarios predict severe drought and water shortage
Climatic changes on our planet, caused by greenhouse gases (mainly carbon dioxide (co2), ozone (o3), nitrous oxide (n2o), methane (ch4) and chlorofluorocarbons (cfcs)), but also by increased solar activity, could cause major problems in a few decades, especially in areas already slightly affected by increasing drought, such as north africa, the entire mediterranean region, the middle east and the southwest of the united states.
A nasa study in which scientists calculated the effects of future climate warming based on the future development of greenhouse gases and increased solar activity shows that faster than originally thought, the amount of precipitation for certain areas will be negatively affected by climate change.
The figures show the future changes in temperature (left) and precipitation (right), calculated for the year 2050. Image: nasa
There are indications that the precipitation pattern is already undergoing a process of change. The mediterranean region, north africa and the middle east in particular are affected by this and are becoming increasingly drier. If this development continues, we could have significant problems in just a few decades, especially with vital water. A large part of the population in these regions could then even be dependent on water aid deliveries, as the necessary water is no longer available in sufficient quantities as an absolute scarce commodity.
Drew shindell, nasa goddard institute for space studies (giss), new york
Already in 2005 and 2006, the spanish and portuguese have suffered from the worst durre (cf. Record heat in spain and portugal) for more than half a century. Several billion euros of crop losses were the result. Despite the fact that the situation has been looming for a long time, southern europe has been very slow to react to the problem.
In spain, more and more new dams are being built, whose levels are sinking ever lower in the face of increasing drought. The precious elixir will continue to be roughly used for tourist strongholds and to irrigate huge areas of arable land. The situation could worsen drastically in the future if no rethinking takes place.
The image of wide green fields in the mediterranean could be gone very soon. Image: pixelquelle
The sun: influential climate factor
The climate system of the earth is too complex to simulate it realistically. Therefore, scientists use mathematical models (global circulation models) to assess known processes and resulting interactions. These are also used to simulate the climate for the next decades, the results represent trends, which cannot represent the future one hundred percent.
Using a new climate model developed on this basis, researchers at the goddard institute found that increased solar activity in the past was partly responsible for a global warming of the earth’s surface and thus also for a change in atmospheric humidity and air circulation. In all likelihood, these changes also led to one of the strongest climate change events of the past, the upper paleogene warm period (65 – 50 million years ago), the so-called petm (palaozan.
The same climate model also indicates that in the future, precipitation could decrease in regions such as the southwestern united states, mexico, parts of north africa, the middle east, the mediterranean region, and even australia. In contrast, an increase in precipitation over the western pacific along the aquator and in parts of southeast asia would be possible. The computer simulation took into account all relevant possible changes in the oceans, ice volume, global weather and atmosphere (such as ozone concentrations), and solar activity, and accurately reproduced the extensive precipitation shifts over the past hundred years.
Since the solar variation data are not quite 100%, the study focused on the position and type of precipitation rather than their exact amount. The increase in solar activity causes more oxygen molecules to decay, increasing the concentration of ozone in the upper atmosphere, which heats up. This in turn leads to changes in the circulation on the earth’s surface, with the result that the surface temperature rises and the earth’s basic precipitation pattern is strengthened. This means that in very humid regions such as the tropics, precipitation increases, while more arid regions receive even less rainfall.
Precipitation in general is very difficult to predict because it is highly subject to many variable factors, but our results clearly show that an increasingly warm global climate brings with it major changes in precipitation.
The scientists also looked at numerous tree rings and sedimentary deposits from the americas, including mexico, peru and the yucatan peninsula. These are reliable witnesses of the historical climate and confirmed a pronounced increase of drought periods in the southern united states, mexico, and other subtropical regions during the last 1200 years, during periods of increased solar activity. These long-term records of increased solar activity are based on the detection of chemical isotopes whose production is directly related to the sun’s brightness.
Strong solar activity could be responsible for warm period 55 million years ago. Image: esa
Learning from europe: climate protection program for a better future
Combating global climate change is one of the key challenges for the 21st century. Despite the additional factor of solar activity, greenhouse gases play a central role in climate change. The international climate policy aims more or unfortunately less (like the usa, china, india, etc.) at the reduction of greenhouse gases.) aims to limit the increase in global greenhouse gas concentrations in the atmosphere in the medium to long term in such a way that the resulting consequences for climate change remain bearable for humans and nature.
The goal of the european community should therefore be the implementation of a sustainable energy supply, which essentially relies on energy saving, increasing energy efficiency and the expansion of renewable energies, while at the same time phasing out nuclear energy. On 10.January 2007, the european commission presented a comprehensive package of measures for a new energy policy strategy for europe to combat climate change and improve the eu’s energy security and competitiveness.
Even if it would be desirable that all countries on this earth deal intensively with possible and quickly realizable measures, europe could set a good example with a jointly adopted catalog of measures and encourage other countries to participate, provided that europe manages to pull on a common international climate rope and not to get bogged down with national sensitivities. The first step with the acceptance catalog was done, now a joint adoption and implementation must also take place.
The package of proposals sets ambitious targets for greenhouse gas emissions and renewable energy. It should contribute to the creation of a true internal energy market and effective regulation of the market. The commission believes that an international agreement for the period after 2012 should lead to a 30% reduction in emissions from industrialized countries by 2020. To demonstrate its seriousness, the commission also proposes that the european union commit to reducing greenhouse gas emissions by at least 20% by 2020, mainly through energy policy measures. The following is a brief excerpt of the most important aspects:
Accelerating the shift to low-carbon energy sources
The commission’s vision is for the eu to maintain its global leadership in renewable energy. It proposes to set a binding target of 20% for the share of renewable energy sources in total energy production by 2020.
To achieve this, all three components of the renewable energy sector must be massively expanded: electricity, biofuels, and heating and cooling. These renewable energy targets will be complemented by a minimum biofuel share of 10%.
In addition, a package of renewable energy regulations planned for 2007 will include measures specifically to require the market penetration of biofuels and renewable energy sources in heating and cooling technologies.
Efficient use of energy
The commission maintains its target of reducing total primary energy consumption by 20% by 2020. If this is achieved, the eu will consume around 13% less energy in 2020 than it does today, saving eur 100 billion in costs and 780 metric tons of energy. And emit 780 tons less co2 per year.
The commission proposes to quickly fuel-efficient introduce vehicles, tighten regulations and better label equipment, improve the energy efficiency of existing buildings in the eu, and make heat and power generation, transmission and distribution more efficient. It also proposes an international energy efficiency agreement. The proposals in these three areas must be supported by a coherent and credible policy.
An international eu energy policy characterized by unity among the member states
The european union cannot achieve its energy policy and climate protection goals on its own. To cooperate with industrialized and developing countries on the one hand, and with energy consumers and producers on the other.
To manage energy crises and actively develop a common energy policy in which member states increasingly speak with one voice with third countries, it will develop effective solidarity strategies. It will seek genuine energy partnerships with suppliers, characterized by transparency, predictability and reciprocity.
Limiting global climate change to 2° celsius
In addition, the commission of the european communities has drafted a communication addressed to the european council to be held in spring 2007, which will decide on an integrated and comprehensive approach to the eu’s policy on energy and climate change. The following is a brief summary:
Reducing greenhouse gas emissions
It is proposed that the eu aims to reduce greenhouse gas emissions from industrialized countries by 30% (compared to 1990 levels) by 2020 through international negotiations. Pending an international agreement, the eu should already make a firm independent commitment to reduce greenhouse gas emissions by at least 20% by 2020 through its emissions trading scheme, other climate change policies and energy policy measures.
With this approach, the eu can demonstrate international leadership on climate ies, signal to industry that the ets will continue after 2012, and call for investment in emission reduction technologies and low-carbon alternatives.
Only effective together
After 2020, developing countries will produce more emissions than developed countries. Until then, emissions in developing countries should increase more slowly overall and then generally decline from 2020 onward. By exploiting the broad range of energy and transport mitigation options that not only significantly reduce emissions, but also deliver immediate economic and social benefits, this goal can be achieved without compromising economic growth and poverty reduction in these countries.
By 2050, global emissions must be reduced by up to 50% from 1990 levels, which means that developed countries must reduce their emissions by 60-80% by that year. Many developing countries will also need to significantly reduce their emissions. The eu and its member states should decide to significantly increase investment in research and development in the areas of energy production and energy saving.