Climate is what we expect, weather is what we get.
The Earth's Climate in the Past
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The Signs of Climate Change
Climate Change's Effects On Temperate Rain Forests Surprisingly ComplexJan. 18, 2013 — Longer, warmer growing seasons associated with a changing climate are altering growing conditions in temperate rain forests, but not all plant species will be negatively affected, according to research conducted by the U.S. Forest Service's Pacific Northwest Research Station.
Research featured in the January 2013 issue of Science Findings -- a monthly publication of the station -- reveals a complex range of forest plant responses to a warming climate.
" Although the overall potential for growth increases as the climate warms, we found that plant species differ in their ability to adapt to these changing conditions," said Tara Barrett, a research forester with the station who led the study.
Barrett and her colleagues explored trends in forest composition in southeastern and south-central Alaska, home to the bulk of the world's temperate rain forests. The researchers found an uptick in growth in higher elevations of the region over the 13-year period, with an almost eight-percent increase in live-tree biomass, a measure of tree growth. Individual species within the rain forest, however, differed -- western redcedar biomass increased by four percent, while shore pine declined by almost five percent.
As forest managers consider climate impacts like these in the management of their forests, scientists, including Barrett and research biologist David L. Peterson, are communicating climate change science within the agency, helping managers -- in Alaska and beyond -- to meet this challenge.
In another research effort, featured in the December 2012 issue of Science Findings, Peterson summarized the scientific basis for climate change adaptation. He and his colleagues across the country have conducted case studies that revealed the critical role of science-management partnerships in adaptation planning and have produced a climate change guidebook and Web portal for climate science information.
" The main objective is to get science in the hands of managers so that they have the basic information, but also have access to the documentation they need to do their jobs," said Peterson.
Astronomer Milutin Milankovitch developed the mathematical formulas upon which these orbital variations are based. He hypothesized that when some parts of the cyclic variations are combined and occur at the same time, they are responsible for major changes to the earth's climate (even ice ages). Milankovitch estimated climatic fluctuations over the last 450,000 years and described cold and warm periods. Though he did his work in the first half of the 20th century, Milankovich's results weren't proven until the 1970s.
A 1976 study, published in the journal Science examined deep-sea sediment cores and found that Milankovich's theory corresponded to periods of climate change. Indeed, ice ages had occurred when the earth was going through different stages of orbital variation.http://geography.about.com/od/learnabouttheearth/a/milankovitch.htm