I suppose it can depend upon when you pick the start of the time period. The following NASA data shows total solar irradiance going up since the mid 1980's:
The following graph shows both irradiance and trending up over the past 100 years: 
Posted on 05/31/2007 11:29:24 AM PDT by grundle
2) You missed this part in the study
Mars' southern ice cap is shrinking and has lost billions of tons of carbon dioxide over just the past 4 Martian years, says Geissler. The team's simulations suggest that the planet's albedo-induced warming may be responsible for as much as 60 percent of that loss.
They are using computer models so no doubt they are putting in the variables to get the numbers they want, but even assuming her numbers are right, what's causing the other 40+ percent?
Sorry but Mars doesn't have ocean currents or any other of the multiple factors that effect weather here on Earth which pretty much means by process of elimination it's solar variability is the only thing left that could have had the effect seen on Mars
Oh yeah they have them, Pluto's though takes the cake
Quote
"Though Pluto was closest to the Sun in 1989, a warming trend 13 years later does not surprise David Tholen, a University of Hawaii astronomer involved in the discovery. "It takes time for materials to warm up and cool off, which is why the hottest part of the day on Earth is usually around 2 or 3 p.m. rather than local noon," Tholen said. "This warming trend on Pluto could easily last for another 13 years."
1st it should be noted; in those 14 years, Pluto due to it's a widely elliptical orbit has moved 250,000 km further away from the sun. That is equal to moving the earth out to the middle of the asteroid field, yet it still heated up. Move Earth out that far between noon and 3 and tell me if it will still continue to heat up.
2nd that's laughable on it's face, the Earth is hottest at 2 or 3pm because that's when the earth is re-radiating the most heat it absorbed, now how in the hell can Pluto which is 1/1000th the size of Earth (not to mention Pluto lacks vast oceans to store vast quantities of heat)continue hold it's heat for 27 years while the much the larger Earth starts to cool off in a few hours?
qam1, great replies (this is one of the highest quality discussions I’ve had on global warming) and I’ll get to some of your other points later (there’s only so many hours in the day and you’re extremely thorough). But just a quick answer to the point that solar variability is the only thing that could cause the dust storms on Mars.
Mars has one of the highest orbital eccentricities of any planet in our solar system which causes much greater seasonal changes than on Earth. Atmospheric pressure fluctuates around 25% between summer and winter which would have strong weather effects. Around the winter solstice, CO2 freezes in the North Pole while the South Pole releases CO2 which causes big differences in atmospheric pressure across the planet. So Mars’ weather is very volatile and doesn’t require solar variations to generate a puff of wind.
qam1, to answer another of your questions:
“Mars’ southern ice cap is shrinking and has lost billions of tons of carbon dioxide over just the past 4 Martian years, says Geissler. The team’s simulations suggest that the planet’s albedo-induced warming may be responsible for as much as 60 percent of that loss.” What’s causing the other 40+ percent?
I think you’ve misread that quote. The 60 percent they’re refering to is 60% loss of CO2 from the southern ice cap, not 60% of temperature rise.
I suppose it can depend upon when you pick the start of the time period. The following NASA data shows total solar irradiance going up since the mid 1980's:
The following graph shows both irradiance and trending up over the past 100 years:
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