Letter to Climate Change Denier; Re: Medieval Warming Period

(Clarification: My husband said it's not clear who I'm talking to in this letter. I'm addressing climate change deniers in general.)

Dear CC Denier,

I don't mean to insult your intelligence. I'm sure you are pretty smart, went to college, and all that. I'm sure you are at least as smart as I am. But climate science is really, really complicated. It's not just common sense. So unless you have a PhD in atmospheric sciences or climatology, please stop confusing yourself by watching Glenn Beck (who only graduated high school by the way). And how about showing a little humility? I mean, I don't see you going around speechifying about nuclear physics, right? But suddenly, you're an expert in planetary phenomena?

Lately, you've been talking your head off about the so-called Medieval Warm Period. You think you've finally found your smoking gun because, you've heard, there was a warm period during the Middle Ages. Therefore, warming cannot be caused by the industrial activities of humans. First, climate data from the 800s to the 1300s is, not surprisingly, incomplete and most scientists decline to draw conclusions from them (for instance, data is limited to certain regions in the world.)

Second, even this limited data shows the temperature are higher now and rising faster. Don't believe me? How about the U.S. National Oceanic and Atmospheric Adminsitration that says,  about the Medieval Warm Period,

"In summary, it appears that the late 20^th and early 21^st centuries are likely the warmest period the Earth has seen in at least 1200 years."

Oh, I just heard that you are now talking about climate warming on Mars! You say that since there are no humans on Mars, the warming disproves that Earth's warming is man-made. You must have just gotten a PhD in astronomy or astrophysics, or maybe a job at NASA. Regardless, congratulations. Now you are forcing me to research Mars's atmosphere. Turns out, Mars has its own thing going on with all sorts of factors absent from Earth, such as violent sand storms. Who knew the planets could be so different! Also, the warming was observed on a particular area of Mars and not necessarily globalized.

I'll stop here because I'm out of my league. But I'm sure we'll talk again later. You know where to find me.

Sincerely,

LaGreenga