Thread: Any doubts about Climate Change?

JMA’s December number is in (warmest December on record),………

The monthly anomaly of the global average surface temperature in December 2015 (i.e. the average of the near-surface air temperature over land and the SST) was +0.67°C above the 1981-2010 average (+1.05°C above the 20th century average), and was the warmest since 1891. On a longer time scale, global average surface temperatures have risen at a rate of about 0.74°C per century.

Five Warmest Years (Anomalies)

1st. 2015 (+0.67°C), 2nd. 2014 (+0.31°C), 3rd. 2006, 1997 (+0.28°C), 5th. 2003 (+0.25°C)

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From Berkeley Earth

2015 Unambiguously the Hottest Year on Record

According to new Berkeley Earth analysis, 2015 was unambiguously the hottest year on record. For the first time in recorded history, the Earth’s temperature is clearly more than 1.0 C (1.8 F) above the 1850-1900 average. 2015 was approximately 0.1 degree C (about 0.2 degrees F) hotter than 2014, which had tied with 2005 and 2010 as the previous hottest years. 2015 set the record with 99.996% confidence. The analysis covered the entire surface of the Earth, including temperatures from both land and oceans. The warming was not uniform, and for the contiguous United States, it was the 2nd warmest year ever (+1.33 C), surpassed only by 2012.

Land and Ocean

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For people waiting for @NASAGISS & @NOAA release of the 2015 temperature analysis, press briefing is Jan 20th at 11am (EST).

Originally Posted by MrG

Originally Posted by S Landreth

So in sum: It appears that we’ve just seen yet another surprise from the climate system — and yet another process, like the melting of Antarctica, that seems to be happening faster than previously expected. And indeed, much like with that melting, the upshot if the trend continues is an especially bad sea level rise for the United States — the country more responsible than any other on Earth for the global warming that we’re currently experiencing.

I remember reading about this idea few years ago. Looks like it is finally coming to pass.

And when more of the permafrost is exposed and starts to thaw, the rise in CO2 is expected to be exponential, with exponential rise in warming.

More trouble



CO2 EQUIVALENTS

Each greenhouse gas (GHG) has a different global warming potential (GWP) and persists for a different length of time in the atmosphere.

The three main greenhouse gases (along with water vapour) and their 100-year global warming potential (GWP) compared to carbon dioxide are:

• 1 x – carbon dioxide (CO2)
• 25 x – methane (CH4) – I.e. Releasing 1 kg of CH4 into the atmosphere is about equivalent to releasing 25 kg of CO2
• 298 x – nitrous oxide (N2O) – I.e. Releasing 1 kg of N2O into the atmosphere is about equivalent to releasing 298 kg of CO2

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A new study confirms,…….if the amount of carbon dioxide in the atmosphere doubles, temperatures will rise between 2°C and 4.5°C, most likely 3°C

Some previous studies claiming that the climate is insensitive to carbon pollution missed a key factor

A new study by Kate Marvel, Gavin Schmidt, Ron Miller, and Larissa Nazarenko at the NASA Goddard Institute for Space Studies appears to have found the answer. They drew upon previous research by Drew Shindell and Kummer & Dessler, who identified a flaw in studies taking the energy budget approach. Those studies had assumed that the Earth’s climate is equally sensitive to all forcings.

In reality, as world-renowned climate scientist James Hansen noted in a 1997 paper, some forcings are more efficient at causing the Earth’s surface temperature to change than others. Those in which the effects are focused in the northern hemisphere tend to be more efficient, for example. Andrew Dessler explains in the video below.

snip

Moreover, it’s worth pointing out that even ‘low’ estimates are not that low. As climate scientist Chris Forest noted, if they were correct, “It might buy us five or ten years” to solve the problem. We’re so far behind the carbon pollution cuts needed to avoid dangerous climate change, that extra decade wouldn’t even be enough. Even if the contrarians were right, we would still need to cut carbon pollution rapidly.

However, the NASA study shows that the previous estimates were indeed biased low, and correcting for that bias brings them into agreement with estimates using other approaches. This result makes it all the more urgent that we ratchet down carbon pollution emissions as quickly as possible to curb the risks associated with rapid climate change.

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The warming trend continues with or without el nino

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How Reliable are Satellite Temperatures?