That has led the Manomet Center for Conservation Sciences to say that the net effect on greenhouse gas emissions is higher.

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HFC, for example, an industrial gas, has 11, 000 times the greenhouse effect of CO2.

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The effect of diminishing sea ice isn't limited to increasing atmospheric greenhouse gas concentrations.

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The gas would soon find its way into the atmosphere, where it would add to the greenhouse effect and cause the temperature to rise.

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