There are many units by which to measure the impact of climate change: degrees of increasing temperature, feet of rising sea lev

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问题     There are many units by which to measure the impact of climate change: degrees of increasing temperature, feet of rising sea level, dollars needed to adapt to a warming world. But a group of scientists in California have put forth an intriguing new unit of measurement: kilometers per year.
    Writing in a paper published in Nature, scientists describe what they call the velocity of climate change, or more specifically, the speed of Earth’s shifting climatic zones. As global temperature rises over the next century, Earth’s habitable(可居住的)climatic zones will start moving too. That means many species of plants and animals will also have to move in order to survive. Whether or not they do will depend on several factors, but two of the most important are how fast a species can adjust its habitat range, and how quickly that range is moving out from under it.
    Until now, ecologists have mostly focused on these factors as they affect individual species, but the new paper takes a more global view. By combining temperature projections on a very fine scale with global topographic(地形的)maps, researchers have predicted change not for specific species, but for the climatic zones they need to keep up with.
    This new index could also prove very useful, especially to conservationists who work to keep species from extinction. While the average velocity of climate change may be a bit less than a half-kilometer per year worldwide, according to the paper, it can be significantly faster or slower depending on the local topography. In deserts and other flat areas, such as the Amazon basin, climatic zones will move faster, while hilly or mountainous terrain will slow things up. In areas with varied terrain including lots of hills, therefore, suitable conditions might be available relatively nearby.
    However, those scientists emphasize that their velocity maps are oversimplifications—at least so far. For one thing, they do not account for the unique characteristics of various species within a given ecosystem. Nevertheless, while the climate-velocity concept is still crude, it’s promising enough that one of the researchers Ackerly is collaborating with an organization called the Bay Area Open Space Council on habitat conservation strategies in central California.
The velocity maps are considered not fully-developed in that they do not specify the unique characteristics of______.

选项

答案various species within a given ecosystem

解析 题干中的in that表原因,即气候变化速度图为什么会被认为不成熟的原因。文中使用For one thing来举例说明原因,故答案可在其后找。
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