The contribution of forestry projects is here discussed on two levels. On a first level, the COz effect of individual projects is analysed. On a second level, the study asks whether the analysis of forestry projects can contribute to questions on climate change which have been discussed in the economic literature during the past two decades. While most studies on forestry projects focus on particular details, predominantly on technical issues, this study takes a rather broad perspective, drawing together different relevant aspects: the stability of international agreements is discussed, costs and benefIts of reducing GHG emissions in industrial countries are reviewed, the underlying causes of deforestation are analysed and insights from resource economics are taken into consideration.
Such a wide perspectiveallows the identifIcation, discussion and appreciation of problems and opportunities associated with forestry projects in the context of climate change which are otherwise not recognised. Virtually every statement on this matter; from the US Office of Technology Assessment, to the National Academy of Science, to the Nairobi Declaration on Climatic Change, includes some recommendation for planting and protecting forests. In fact, forestry is intimately involved in the climate change debate for several reasons: changing climate patterns will affect existing forests, tropical deforestation is one of the major sources of greenhouse gases to the atmosphere, reforestation projects could remove additional carbon dioxide from the atmosphere and there is renewed interest in wood-based or other renewable fuels to replace fossil fuels.
Part of the enthusiasm for forestry-related strategies in a greenhouse context is the perception that forests not only provide greenhouse benefits but also serve other desirable social objectives. This discussion will explore the current range of thinking in this area and try to stimulate additional thinking on the rationality of the forestry-based approaches and the challenges posed for US forestry.
Author : U. These concerns have prompted governments around the world to commission technical assessments on the impact of climate change on the environment and the economy. Based on the current scientific information within these assessments, governments have initiated negotiations on policy action to reduce greenhouse gas emissions and to address the vulnerabilities of the ecological, economic, and social systems to climate change.
Critical to policy formulation is a periodic synthesis of the ever-expanding knowledge on forest ecology, the impact of climate on the forests and of forests on climate, forest management, the socio-economic value of trees and forests, and the role of forests in the global carbon cycle.
The structure of these periodic assessments allows for the synthesis and integration of the current state of scientific knowledge. He was familiar with the works of J. Fourier and J. Tyndall , but found it necessary to formulate his own idea of the experiment: «In order to get an idea of how strongly the radiation of the earth or other body of the temperature 15 oC is absorbed by the quantities of water vapour or or carbonic acid in the proportions in which these gases are presented in our atmosphere, one should, strictly speaking, arrange experiments on the absorption of heat from a body at 15o by means of appropriate quantities of both gases.
In fact, it is not clear how to carry out such an experiment, nor what kind of equipment the author had in mind. It is possible to measure the absorption of radiation by gases if there is a radiation source, a closed vessel with a gas through which radiation passes, and a sensor that registers the intensity of radiation transmitted through the gas. If the author had in mind the absorption of heat by gases, then, according to the law of thermodynamics, such absorption is possible only if the temperature of the gas is lower than the temperature of the said body.
It is not surprising that such an experiment was not carried out either by Arrhenius himself or by his followers over the past years. Arrhenius's hypothesis about the greenhouse effect was based not on experimental studies of the Earth's atmosphere, but on the astronomical observations of S. Langley, who 10 years earlier tried to determine the temperature of the Moon based on the spectrum of moonlight. On the one hand, heat suffers a selective diffusion on its passage through the air; on the other hand, some of the atmospheric gases absorb considerable quantities of heat.
These two actions are very different. From this quote it can be seen that Arrhenius completely equates radiation and heat. Neither in the time of Arrhenius, nor now there was and there is no theoretical analysis of the relationship between the radiation wavelength and scattering.
However, the theory of heat was at that time developed in detail and presented in the monograph of the same name by J. By the time Arrhenius's article was published, the posthumous edition of Maxwell's book had already been published, edited by the outstanding physicist of the time, Lord Rayleigh, and an online edition of is now available 3. Caryl-Sue, National Geographic Society. Dunn, Margery G.
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Global temperatures and sea levels are rising, and possibly contributing to larger more devastating storms. This can all be contributed to climate change. Climate change is defined as gradual changes in all the interconnected weather elements on our planet over approximately 30 years.
The data shows the Earth is warming and it's up to us to make the changes necessary for a healthier planet. Use these resources in your classroom to help your students understand and take action on climate change. The Industrial Revolution was the transition from creating goods by hand to using machines.
Its start and end are widely debated by scholars, but the period generally spanned from about to According to some, this turning point in history is responsible for an increase in population, an increase in the standard of living, and the emergence of the capitalist economy. Teach your students about the Industrial Revolution with these resources. The weather you encounter day to day depends on where you live.
Places around the Equator experience warm weather all year round, but experience alternate periods of rainy and dry seasons. Places near lakes may experience more snow in the winter, whereas places on continental plains may be more prone to hail, thunderstorms, and tornados in the summer. Learn more about regional climates with this curated resource collection. An atmosphere is the layers of gases surrounding a planet or other celestial body. These gases are found in layers troposphere, stratosphere, mesosphere, thermosphere, and exosphere defined by unique features such as temperature and pressure.
The atmosphere protects life on earth by shielding it from incoming ultraviolet UV radiation, keeping the planet warm through insulation, and preventing extremes between day and night temperatures. The sun heats layers of the atmosphere causing it to convect driving air movement and weather patterns around the world.
Teach your students about the Earth's atmosphere with the resources in this collection. Carbon dioxide, a key greenhouse gas that drives global climate change, continues to rise every month. Find out the dangerous role it and other gases play. The Earth is warming up, and humans are at least partially to blame. The causes, effects, and complexities of global warming are important to understand so that we can fight for the health of our planet.
Join our community of educators and receive the latest information on National Geographic's resources for you and your students. Skip to content. Twitter Facebook Pinterest Google Classroom. Encyclopedic Entry Vocabulary. Some of the suggestions for adapting include: Expanding water supplies through rain catchment , conservation , reuse, and desalination.
Adjusting crop locations, variety, and planting dates. Building seawall s and storm surge barrier s and creating marsh es and wetland s as buffer s against rising sea levels. Creating heat-health action plan s, boosting emergency medical services, and improving disease surveillance and control.
Diversifying tourism attractions, because existing attractions like ski resort s and coral reef s may disappear. Strengthening energy infrastructure , improving energy efficiency, and reducing dependence on single sources of energy.
The lonely polar bear—the unofficial mascot of global warming. European Union. Fossil fuels formed from the remains of ancient plants and animals.
Great Plains. Industrial Revolution. Kyoto Protocol. Also called a bulkhead. United Nations Environment Programme. World Meteorological Organization.
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Related Resources. Climate Change. View Collection. The Industrial Revolution. Regional Climate. The Greenhouse Effect and our Planet. View leveled Article.
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