Tuesday, April 2, 2013
That difficult term "Climate Sensitivity"
Climate sensitivity may be defined as projected response of global surface temperature to radiative forcing, or a factor affecting net radiative forcing, usually CO2 emissions. See also the Wiki definition
That said, the words climate and sensitivity have so much baggage that news media have a hard time translating in a conversation about climate sensitivity.
- only marks an atmospheric surface temperature change.
- does not directly indicate change in heat content of materials, most significantly the ocean.
- does not correlate temperature or heat content to dynamic climate phenomena.
- does not have a standardized time frame.
- does not provide indicators at a regional scale, yet the pace and extremity of temperature change differs greatly from latitude to latitude, land to sea, and so on.
I'd like to see a work-up on "heat content sensitivity" which could describe the more direct relationship between greenhouse gas and the increased heat content of the globe, which varies by region and substance.
The temperature estimates for "climate sensitivity" all have to be derived from the heat content and from there to other dynamics about heat distribution.
Heat content sensitivity is related to very useful questions. Imagine having better predictors for when glaciers melt, water vapor rises from a lake or ocean, or locating places that would fail to cool off enough at night for plant or animal survival.
As it stands now, "climate sensitivity" yields an unwieldy factoid, an average global temperature shift. Nobody is going to get excited about average 2 degrees Celsius, but Whoa, if that means that some parts of the planet have heated up into the realm of heat exhaustion and heat shock, or the ocean has warmed up so widely that dynamic superstorms are common arrivals on land, and on and on, some of us might get agitated.
Even though we can measure temperature, temperature is a proxy for other changes taking place.
In a child with a fever, the physiology, immunology and chemistry are far more complex than just being warmer. Like the child, a raised temperature of the planet is a clue that complex changes have already taken place as well as acting as indicator for what is to come.