Human climate role foreseen

To Ms. Madsen (“Climate fear hard to swallow,” Letters, Feb. 15), it appears that there were some misunderstandings of the journal article you cited. This article attempts to understand climate change by looking at the Little Ice Age, a period stretching from 1650 to 1850 (before mass industrialization). Their conclusion: “These results highlight the sensitivity of high-altitude tropical regions to relatively small changes in radiative forcing, implying even greater probable responses to future anthropogenic forcing.” In other words, these glaciers are even more sensitive to human changes to the environment than previously thought.

Though it is true that the article claims “solar activity has exerted a strong influence on century-scale tropical climate variability during the late Holocene,” it concludes by stating that “conservative estimates of net anthropogenic greenhouse-gas radiative forcing for the next 50 years surpass that of solar forcing in previous centuries, implying that profound climatic impacts can be predicted for tropical montane regions.”

Solar radiation certainly plays an important part in global climate change. However, greenhouse gas emissions produced by people in the next 50 years is what will determine how much of that solar energy becomes trapped within our atmosphere and the extent of global climate change.

Alex Peterson

Spokane