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Volume 1 Number 2:  1 October 1998

Editorial
Show Us the Science: This simple phrase -- show me the money -- is a powerful expression that reaches far beyond the movie screen.  It is the bottom line of nearly all business negotiations, the place where the rubber truly meets the road.  Likewise, in essentially all fields of endeavor, there typically is some overriding and all-powerful criterion upon which we base our decisions.  And in this regard, concern for the environment should be no different; but instead of "show me the money," the operative phrase when dealing with the future of the biosphere should clearly be "show me the science."...

Journal Reviews
Millennial-Scale Changes in Ocean Circulation: Sediment cores retrieved from the North Atlantic Ocean reveal the existence of millennial- and orbital-scale cycles in ocean circulation dynamics that may have similar cyclical impacts on climate.

Decadal-Scale Changes in Ocean Circulation: Hydrographic data are used to demonstrate that the outflow of deep water from the Nordic seas to the Atlantic Ocean has risen and fallen by a factor of two over the past forty years, with flow rates generally decreasing with increasing polar air temperatures.  Implications of this phenomenon for global climate are discussed.

Effects of Atmospheric CO2 on Hurricanes: The authors review the scientific literature pertaining to possible changes in tropical storms, hurricanes and extreme rainfall events that might occur in response to potential CO2-induced global warming as predicted by state-of-the-art climate models.  They find little about which to feel confident.

Effects of Hurricanes on Atmospheric CO2: A study of the effects of hurricanes on the air-sea exchange of CO2 reveals that they play an important role in earth's global carbon cycle, influencing the greenhouse properties of the atmosphere in ways that had not previously been anticipated by global climate models.

Effects of Atmospheric CO2 on Apple: One-year-old apple trees that received atmospheric CO2 enrichment for eight days exhibited enhanced rates of photosynthesis despite the fact that photosynthetic down regulation occurred.

Photosynthetic Acclimation of Birch Trees to Elevated CO2: Silver birch trees rooted in the ground and grown for four years at a CO2 concentration of 700 ppm in open-top chambers located in England continued to exhibit greater photosynthetic rates than trees grown in normal air, despite the fact that they displayed signs of photosynthetic acclimation to elevated CO2.

Responses of Oak Trees to Long-Term Atmospheric CO2 Enrichment: Elevated CO2 concentrations of 500 to 1000 ppm derived from natural springs located in central Italy significantly stimulated photosynthesis in mature oak trees that were 15 to 25 years old.  Water-use-efficiency was also greatly increased by the elevated CO2, thereby enabling the trees to better withstand extended periods of drought and to expand their ranges as the air's CO2 content rises.

Woody Plants Expand Their Ranges: A Response to CO2?: An assessment of vegetative cover change over a period of 23 years in a protected natural research area in central Oregon (USA) has shown trees and shrubs to be replacing herbs and grasses, consistent with experimental observations that suggest that woody plants are more responsive to the ongoing rise in the air's CO2 content than are non-woody plants.

Old Trees in Ancient Forests: A study of large rainforest trees in Brazil has demonstrated that, if preserved, they can remove massive amounts of CO2 from the air for far longer than anyone expects the "age of fossil fuels" to persist, thus providing an effective natural "brake" on the rate of rise of the air's CO2 content.

Atmospheric CO2 and Soil Nitrogen Effects on Pine Tree Growth: A large research effort composed of numerous individual experiments has revealed that ponderosa and loblolly pine trees growing in soils that are moderately deficient in nitrogen may have their growth rates enhanced by as much as 1,000% by a doubling of the air's CO2 concentration.

Interactive Effects of CO2 and Nitrogen on Longleaf Pine Trees: In this 20-month study of longleaf pine tree seedlings, a doubling of the air's CO2 content had no effect on whole-tree biomass at low soil nitrogen levels; but at high soil nitrogen it increased the trees' biomass by 42%.

Interactive Effects of CO2 and Nitrogen on Ponderosa Pine Trees: Ponderosa pine tree seedlings rooted in the ground within open-top chambers exhibited little response to atmospheric CO2 enrichment or soil nitrogen content after one growing season.  After two growing seasons, however, seedlings exposed to 700 ppm CO2 had significantly more above- and belowground biomass than did seedlings exposed to ambient air, regardless of soil nitrogen content.

CO2 Uptake by Terrestrial Vegetation: A "progress report" on our understanding of earth's global carbon cycle reveals that terrestrial vegetation is currently a major sink for anthropogenically-produced CO2, and that, in this role, the world's land plants could profoundly impact the climatic consequences of mankind's CO2 emissions.