Sentences with phrase «albedo slow feedbacks»

Figure 1: Schematic diagram of the equilibrium fast - feedback climate sensitivity and Earth system sensitivity that includes surface albedo slow feedbacks.

Not exact matches

The resulting slow GHG and albedo feedbacks are about 3 W / m2 each, in his calculation.

This chemical weathering process is too slow to damp out shorter - term fluctuations, and there are some complexities — glaciation can enhance the mechanical erosion that provides surface area for chemical weathering (some of which may be realized after a time delay — ie when the subsequent warming occurs — dramatically snow in a Snowball Earth scenario, where the frigid conditions essentially shut down all chemical weathering, allowing CO2 to build up to the point where it thaws the equatorial region, at which point runaway albedo feedback drives the Earth into a carbonic acid sauna, which ends via rapid carbonate rock formation), while lower sea level may increase the oxidation of organic C in sediments but also provide more land surface for erosion... etc..

Plotting GHG forcing (7) from ice core data (27) against temperature shows that global climate sensitivity including the slow surface albedo feedback is 1.5 °C per W / m2 or 6 °C for doubled CO2 (Fig. 2), twice as large as the Charney fast - feedback sensitivity.»

As I understand Hansen he's saying: if we double CO2 this century (so upto about 550 - 600 ppm), that will mean a forcing of about 4 W / m2 and 3 degrees C warming in the short term (decades), and thru slow feedbacks (albedo + GHG) another 4 W / m2 and 3 degrees in the long term (centuries / millennia).

Slow insolation changes initiated the climate oscillations, but the mechanisms that caused the climate changes to be so large were two powerful amplifying feedbacks: the planet's surface albedo (its reflectivity, literally its whiteness) and atmospheric CO2 amount.

I would like to see a discussion of the likelihood that factors traditionally viewed as slow response feedback factors (such as Arctic albedo, or high methane emissions permafrost degradation) may actually become faster response feedback factors.

[1] CO2 absorbs IR, is the main GHG, human emissions are increasing its concentration in the atmosphere, raising temperatures globally; the second GHG, water vapor, exists in equilibrium with water / ice, would precipitate out if not for the CO2, so acts as a feedback; since the oceans cover so much of the planet, water is a large positive feedback; melting snow and ice as the atmosphere warms decreases albedo, another positive feedback, biased toward the poles, which gives larger polar warming than the global average; decreasing the temperature gradient from the equator to the poles is reducing the driving forces for the jetstream; the jetstream's meanders are increasing in amplitude and slowing, just like the lower Missippi River where its driving gradient decreases; the larger slower meanders increase the amplitude and duration of blocking highs, increasing drought and extreme temperatures — and 30,000 + Europeans and 5,000 plus Russians die, and the US corn crop, Russian wheat crop, and Aussie wildland fire protection fails — or extreme rainfall floods the US, France, Pakistan, Thailand (driving up prices for disk drives — hows that for unexpected adverse impacts from AGW?)

Equilibrium sensitivity, including slower surface albedo feedbacks, is 6 °C for doubled CO2 for the range of climate states between glacial conditions and ice - free Antarctica.»

The resulting slow GHG and albedo feedbacks are about 3 W / m2 each, in his calculation.

Simple physics dictates that with less sea ice there is magnified warming of the Arctic due to powerful albedo feedback; this in turn reduces the equator to pole temperature gradient which slows the jet stream winds causing them to become more meridional; this combined with 4 % more water vapor in the atmosphere (compared to 3 decades ago) is leading to much more extremes in weather.

In their latest Science paper submittal Jim Hansen, et al. argue that we must reduce atmospheric CO2 to below 350 ppm because so - called «slow feedbacks» such as changes in ice sheet albedo are occurring much faster than expected.

The problem in the «slow» feedback analysis is that it seems a never - ending runaway: there are positive feedbacks (ice melting, carbon pump saturation); which imply less albedo, more CO2; which imply new positive feedbacks (more ice melting, more carbon pump saturation)... and so on.

All of these have albedo effects and all are «slow» feedbacks which are considerably more sensitive than we expected — given a variety of feedbacks which we hadn't even been aware of before.

Based on evidence from Earth's history, we suggest here that the relevant form of climate sensitivity in the Anthropocene (e.g. from which to base future greenhouse gas (GHG) stabilization targets) is the Earth system sensitivity including fast feedbacks from changes in water vapour, natural aerosols, clouds and sea ice, slower surface albedo feedbacks from changes in continental ice sheets and vegetation, and climate — GHG feedbacks from changes in natural (land and ocean) carbon sinks.

Slow insolation changes initiated the climate oscillations, but the mechanisms that caused the climate changes to be so large were two powerful amplifying feedbacks: the planet's surface albedo (its reflectivity, literally its whiteness) and atmospheric CO2 amount.

There are, however, also slow feedbacks like the change in surface albedo from the reduction of snow cover that contribute to TCS / ECS.

The remaining slow drift to lower GMT and pCO2 over glacial time, punctuated by higher - frequency variability and the dust − climate feedbacks, may reflect the consequences of the growth of continental ice sheets via albedo increases (also from vegetation changes) and increased CO2 dissolution in the ocean from cooling.

Hansen & Sato [60] suggest adding slow feedbacks one by one, creating a series of increasingly comprehensive Earth system climate sensitivities; specifically, they successively move climate - driven changes in surface albedo, non-CO2 GHGs and CO2 into the feedback category, at which point the Earth system sensitivity is relevant to an external forcing such as changing solar irradiance or human - made forcings.

In other words, if the Greenland / Antarctic surface albedo change were identified as a slow feedback, rather than as a fast - feedback snow effect as it is in figure 7, the fast - feedback sensitivity at 1 — 4 × CO2 would be approximately 4 °C.

Glacial — interglacial oscillations of the CO2 amount and ice sheet size are both slow climate feedbacks, because glacial — interglacial climate oscillations largely are instigated by insolation changes as the Earth's orbit and tilt of its spin axis change, with the climate change then amplified by a nearly coincident change of the CO2 amount and the surface albedo.

If anyone can explain how a glacial cycle can suddenly come to an end through a slow GHG / albedo feedback / forcing, I'd greatly appreciate it.

What happened in the Arctic, was a slow, very slow and gradual decrease in cooling, caused by progressively longer warmer seasons, with a feedback loop of warm air reducing albedo, with reduced albedo increasing warm air.

As I understand Hansen he's saying: if we double CO2 this century (so upto about 550 - 600 ppm), that will mean a forcing of about 4 W / m2 and 3 degrees C warming in the short term (decades), and thru slow feedbacks (albedo + GHG) another 4 W / m2 and 3 degrees in the long term (centuries / millennia).