Sentences with phrase «end runaway greenhouse»

On the other hand, conceivable levels of human - made climate forcing could yield the low - end runaway greenhouse.

This has been reinforced with increasing urgency by scientists around the world, with US climate scientist James Hansen this week publishing a paper highlighting that «conceivable levels of human - made climate forcing could yield the low - end runaway greenhouse effect» including «out - of - control amplifying feedbacks such as ice sheet disintegration and melting of methane hydrates».

then @ 191 accuse UN IPCC / climatology of «unconscionable and a dereliction of responsibility» How this accusation links with your comment @ 192 where climatology harnesses the expletive & Hansen's pronouncement that a human - fueled «low - end runaway greenhouse» is «conceivable» — how this links in is not made plain.

Not exact matches

If the planet is only one Earth mass, Jenkins says, any life there might be near its end; the world would be on the verge of a runaway greenhouse effect, with gravity too weak to prevent its life - giving water from boiling off into space due to rising surface temperatures.

The idea is that runaway greenhouse effects derived from the (end - Permian) eruption of the Siberian Traps and the (end - Cretaceous) asteroid impact and / or eruption of the Deccan Traps contributed to these extinctions which evidently did remove > 50 % of species.

There's also a number of interesting applications in the evolution of Earth's atmosphere that branch off from the runaway greenhouse physics, for example how fast a magma - ocean covered early Earth ends up cooling — you can't lose heat to space of more than about 310 W / m2 or so for an Earth - sized planet with an efficient water vapor feedback, so it takes much longer for an atmosphere - cloaked Earth to cool off from impact events than a body just radiating at sigmaT ^ 4.

John Davies concludes: «The world is probably at the start of a runaway Greenhouse Event which will end most human life on Earth before 2040.»

The extreme end of this, at very large optical depth throughout a deep part of the atmosphere, is when the OLR slope flattens out to a horizontal line and the outgoing emission becomes completely decoupled from the surface temperature, which is when a runaway greenhouse can kick in.

Venus succumbed early to a «runaway water vapor greenhouse,» in which the increased water vapor content arising from increased temperature reached an end state with much of the ocean evaporated into the atmosphere.

We will learn some things about the CO2 greenhouse effect you have probably never heard in the media, such as the fact that warming from CO2 is actually a diminishing return phenomenon whose effect is asymptotic or essentially capped, making it hard to understand the prevalence of wild, open - ended temperature runaway scenarios.

The runaway greenhouse effect has several meanings ranging from, at the low end, global warming sufficient to induce out - of - control amplifying feedbacks, such as ice sheet disintegration and melting of methane hydrates, to, at the high end, a Venus - like hothouse with crustal carbon baked into the atmosphere and a surface temperature of several hundred degrees, a climate state from which there is no escape.

Since no such effect has been observed or inferred in more than half a billion years of climate, since the concentration of CO2 in the Cambrian atmosphere approached 20 times today's concentration, with an inferred mean global surface temperature no more than 7 ° K higher than today's (Figure 7), and since a feedback - induced runaway greenhouse effect would occur even in today's climate where b > = 3.2 W m — 2 K — 1 but has not occurred, the IPCC's high - end estimates of the magnitude of individual temperature feedbacks are very likely to be excessive, implying that its central estimates are also likely to be excessive.

The IPCC overstates temperature feedbacks to such an extent that the sum of the high - end values that it has now, for the first time, quantified would cross the instability threshold in the Bode feedback equation and induce a runaway greenhouse effect that has not occurred even in geological times despite CO2 concentrations almost 20 times today's, and temperatures up to 7 ºC higher than today's.