[millerski150]

I'm reading between the lines a bit. The theory of global warming is that the world's average temperatures are rising. The warming has been attributed in part to rising C02 levels.

Because winters consume the most energy of any season (in the article) to heat, we emit the most c02 during that season.

Given that the planet is warming, the winters are milder (quoted above) (see this article on 13 of the hottest years on record have occurred in the last 15). Because winters are milder (because global warming), they require less energy to produce for heating.

The section I'm referring to is: ""However, CO2 emissions during January-March 2012 were low due to a combination of three factors: A mild winter that reduced household heating demand and therefore energy use"

[bromley]

Average temperatures aren't a great predictor of energy consumption. Yes, warmer winters mean less heating requirement, but warmer summers mean greater cooling requirement. Not such a factor for Jan-Mar in the US, admittedly.

Typically heating and cooling degree days (temperature variations integrated over time) are used to normalize energy consumption data for the weather. Not average temperatures.

[millerski150]

I wasn't trying to focus on energy consumption as much as the fact warming is happening in general, which isn't good. My point was the article title and data set (March - Jan) could mislead one to think global warming is reversing because of lower C02 levels from the winter. I'm saying it's likely not reversing, because the planet is warming overall and warmer summers will cause more energy production (like you said) and, overall, especially when you account for other nations, C02 production is still rising annually. Unfortunately, we only have one atmosphere and planet.

[mhb]

The mild winter is an effect because of the time period at which they're looking. Without additional data, one might expect that global warming implies both warmer winters and warmer summers.

Total heating in winter uses more energy than cooling in summer because there is a bigger difference between the outdoor temperature and the target temperature in winter than in summer. Just based on this article, one would expect the delta of warmer winters and warmer summers to roughly offset each other.

So it doesn't seem sound to conclude, based on this article, that, if the CO2 emissions were looked at over a full year, that the warmer winter would result in a net CO2 reduction.

[bromley]

Also, cooling systems are generally less efficient than heating systems, which would increase summer energy consumption (and CO2) more than the reduction in winter.

That's assuming the overall US climate (by which I mean population- or energy-consumption-weighted degree days) necessitated similar amounts of winter heating and summer cooling.

[millerski150]

I agree global warming does imply warmer winters and summers. I'm not sure if you're addressing the article or what I wrote, but if you look at C02 emissions over a full year, I doubt the warmer winter would result in a reduction of total annual C02 production, because summers will now require more energy & C02 (to cool). I'm saying the title is misleading because just because a small reduction in the US' winter's C02 doesn't mean the planet is cooling (or global warming is reversing) ... especially if you factor in developing world emission growth, which I didn't mention before.