Thursday, April 15, 2021

The world will break through the more ambitious Paris climate target of 1.5 degrees as soon as 2030 but may still avoid a more catastrophic 2 degrees of warming if governments act immediately to dramatically reduce emissions, according to a new report.

Just another prophecy based on guesswork and bound to be as wrong as all the ones before it

The Climate Council report, Aim High, Go Fast, is based on new data from the Intergovernmental Panel on Climate Change and echoes similar findings by the Australian Academy of Science issued last week, but has prompted a dissenting report from one prominent Australian climate scientist, Bill Hare.

It warns that the more ambitious Paris target of holding warming to 1.5 degrees above pre-industrial levels cannot be achieved without what it calls “significant overshoot” and “drawdown”. Drawdown refers to the possibility of using as yet non-existent large-scale carbon dioxide removal technology to help cool and stabilise the climate after overshooting the target.

In the report the Climate Council says that in view of Australia’s historical contribution to global warming, its high emissions and its natural advantages in renewable energy generation, the government should now aim to reduce emissions by 75 per cent below 2005 levels by 2030 and reach net zero by 2035.

So far the government has committed to reducing emissions by 26-28 per cent by 2030 and has set no net-zero target, but said it would prefer to reach that milestone earlier than 2050.

Barrier Reef doomed as up to 99% of coral at risk, report finds
Prime Minister Scott Morrison is expected to face more pressure to commit to more ambitious actions at a climate summit to be hosted by United States President Joe Biden next week and during the lead-up to the next UN climate talks in Glasgow in November.

Asked if such an abrupt reduction was possible, one of the report’s authors, executive director of the Australian National University Climate Change Institute Will Steffen, cited the example of allied nations transforming their economies in five years to defeat the Axis power in World War II.

“The point is, it’s going to be a tough decade, no doubt about it,” he said. “There’ll be some disruption soon, but it’ll be an exciting decade and it’ll set us up for a much brighter future after 2030.”

To reach such targets Professor Steffen said the government would need to immediately halt the expansion of coal and gas and plan to support affected communities as fossil fuels were phased out. Secondly, Australia would have to reach almost 100 per cent renewables in its energy system by 2030.

The report finds “multiple lines of evidence” that the world will break through 1.5 degrees: the increasing pace at which the world has been warming since 2016; new scientific understanding of the climate system’s sensitivity; and the increasing rate of sea levels rising. There is also an analysis of global greenhouse gas emissions which are now in line with the highest of four scenarios considered in the fifth assessment of the Intergovernmental Panel on Climate Change, the UN’s lead climate change body.

“We now face a more dangerous future, with further risks and damages locked in,” says the report.

“We have reached the endgame and if we are to limit further disruption then we must dramatically step up the scale and pace of action. Inaction or delay in the face of so much evidence is in fact an active commitment to massive global climate disruption and damage.”

Counting the increasing costs of droughts and flooding rains
Professor Steffen said the impact of temperature rises did not go up in a linear fashion, and that 2 degrees of warming was far worse than 1.5 degrees.

“The issue here is that past inaction on climate change has cost us dearly. There is plenty of momentum in the climate system, it is like trying to turn a battleship around,” he said.

“The mantra I keep going back to is that every tenth of a degree matters.”

But Bill Hare, a lead author on the fourth IPCC assessment and founder of Climate Analytics, said he believes both the Climate Council and the Australian Academy of Science had found further evidence for the need for immediate and dramatic action. But he did not agree with the view that holding global temperatures rises to 1.5 degrees was virtually impossible.

His dissenting report, co-authored by his colleague Dr Carl-Friedrich Schleussner, said it is not possible to draw conclusions on temperature rises over short time periods used by the Climate Council report; that sea level rise is a lagging rather than leading indicator of climate change; and that the Climate Council had made mistakes in its interpretation of so-called carbon emissions budgets. They further question the report’s analysis of climate sensitivity.

“The evidence presented in the Climate Council of Australia report itself does not support their claim that 1.5°C will be exceeded,” they write.

Mr Hare told the Herald and The Age he believed the evidence of physics and economics showed that 1.5 degrees was still achievable and that the target itself was a critical policy tool supporting international efforts to tackle climate change.

“[The 1.5 degree target] has become mainstream in the global climate debate, it is why nations are talking about net zero by 2050 rather than 2070.”


NASA measures direct evidence humans are causing climate change

The so-called "direct evidence" is in fact a series of estimates, with all the frailties inherent in that. Viscount Mockton comments:

"The paper says that previously the Earth's energy imbalance was detected by models, and then says that it is now detected by "radiative kernels" - which are models. Same difference.

Actually, radiative imbalance is measured both by satellites and by the ARGO bathythermographs. The paper on which IPCC (2021) will chiefly rely, Von Schuckmann et al. (2020), finds the radiative imbalance - i.e., the fraction of the total forcing in recent decades that has not yet resulted in warming - to be 0.87 Watts per square meter. Of this, 70% is anthropogenic (Wu et al. 2019, Scafetta 2021), so that the anthropogenic contribution to the imbalance is 0.61 Watts per square meter - if anything, a little more than the 0.53 given in the paper now being spun by the Marxstream media.

One can work out equilibrium sensitivity to doubled CO2 directly from this imbalance, together with a few other items of data: it is equal to 0.7 x 1.04 x 3.52 / (3.2 - 0.7 x 0.87), or 1.0 K, not the almost 4 K imagined by official climatology."

It may come as a surprise, given the extensive body of evidence connecting humans to climate change, that directly-observed proof of the human impact on the climate had still eluded science. That is, until now.

In a first-of-its-kind study, NASA has calculated the individual driving forces of recent climate change through direct satellite observations. And consistent with what climate models have shown for decades, greenhouse gases and suspended pollution particles in the atmosphere, called aerosols, from the burning of fossil fuels are responsible for the lion's share of modern warming.

In other words, NASA has proven what is driving climate change through direct observations — a gold standard in scientific research....

What NASA has done in this study is to calculate, or quantify, the individual forcings measured from specialized satellite observations to determine how much each component warms or cools the atmosphere. To no one's surprise, what they have found is that the radiative forces, which computer models have indicated for decades were warming the Earth, match the changes they measure in observations.....

Specifically, this study has been able to calculate solid numbers for the changes in heat trapped in the Earth system from the individual contributors that influence heat transfer, like radiation, clouds and water vapor, for the period 2003-2019. The researchers did that by analyzing satellite observations and applying what they call "radiative kernels" to disentangle the various components controlling the transfer, absorption and emission of heat inside the Earth system and what is sent back out into space. Up to this point, satellite observations of Earth's radiation budget had only measured the sum total of radiation changes, not the individual components.

Then there are also feedbacks in the climate system which account for a smaller but still important amount of warming. One example of this is the fact that as the atmosphere warms it can hold more water vapor, and that means it can trap more heat, further allowing for more water vapor to build up. This is a positive feedback which perpetuates warming.




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