Posts Tagged ‘keeling curve’
the curbing emissions front 2- problems both environmental and political
Young people, indeed, all people, need to understand that they cannot solve the energy and climate problem without addressing the special interest problem in Washington.
James Hanson, climate scientist
There are wet and dry heat waves. The wet ones are also known as wet bulb events. Dry heat waves are generally driven by large high pressure systems. From Wikipedia,
High-pressure systems are frequently associated with light winds at the surface and subsidence through the lower portion of the troposphere. In general, subsidence will dry out an air mass by adiabatic or compressional heating. Thus, high pressure typically brings clear skies.
The wet bulb events are of most immediate concern. For example, Karachi in Pakistan experienced one in July 2015, with heat stroke killing some 1200 people in a 10-day ‘pressure cooker’. The wet bulb idea refers to the fact that in a humid environment our sweat has less chance of evaporating and cooling us down. It’s defined much more specifically, though – the wet-bulb temperature is ‘the lowest temperature that can be reached under current ambient conditions by the evaporation of water only.’ No, I don’t know what this means either. Apparently there’s such a thing as a wet-bulb thermometer, but that doesn’t help. What is adiabatic cooling? That’s when air is cooled by expansion without any heat exchange with the surrounding environment. Why do I even mention this? I do understand, I think, that when air, or anything, expands, it likely cools, just as when it’s compressed, it heats up. But this surely involves heat exchange. Or the heat ‘dissipates’, is less ‘concentrated’ as it spreads. I don’t know if this is heat exchange or not. I wish I’d never heard of wet bulb events, but I think I can understand that humid heat would be more harmful to humans than dry heat.
Changing the subject, ice is melting at the poles and sea levels are rising, and don’t forget ocean acidification. And the USA, perhaps the biggest national contributor to the problem, which under Trump is happy to exacerbate things (pity about a politico-social system more or less designed for dictators and their mega-wealthy enablers), is likely to do a lot of the irreparable over the next few years. But on sea level rise, many of our largest cities are essentially ports, including the USA’s oil ports, Houston and Galveston. Other threatened ports are in Saudi Arabia, China, South Korea and Russia. Singapore is also in the firing, or drowning line. And of course all of Australia’s major cities are by the sea.
Rising ocean levels are of course long-term (and likely permanent) stuff. In the short-term, that’s to say right this minute, England and western Europe is experiencing a heat wave, and Alaska has recently received a heat advisory for the first time in its history. And we’re not long into summer, and if I’m not mistaken there will be another summer next year, and so forth. Meanwhile the Joke Bogans and their supporters, the one-winged neoliberal ‘think tanks’ with their deep pockets and narrow self-serving concerns, are spruiking denialism and disinformation at every opportunity. Unsurprisingly, much of this disinformation is manufactured and consumed in the USA, as Wikipedia reports:
A 2022 study found that the public in many countries substantially underestimates the degree of scientific consensus that humans are causing climate change. Studies from 2019–2021 found scientific consensus to range from 98.7–100%. Research found that 80–90% of Americans underestimate the prevalence of support for major climate change mitigation policies and climate concern. While 66–80% Americans support these policies, Americans estimate the prevalence to be 37–43%. Researchers have called this misperception a false social reality, a form of pluralistic ignorance.
This, I feel, is due to the noise made by vested interests, which many wrongly believe to be about genuine climate change scepticism rather than business-as-usual cynicism. A major perpetrator of this cynicism here is Sky News Australia, and the oligarchs who fund it, and of course there are plenty of others. Gina Rinehart, Campbell Newman, Colin Boyce and Hugh Morgan are some of the culprits, but there are many others. Some even try to claim that we’ll be saved by ‘the next ice age’. They can’t effectively deny the current record-breaking temperatures so they try the ‘scientific’ line that it’s part of a natural cycle, somewhat like the Milankovich cycles I’ve written about previously, or the solar magnetic cycle, an 11 year cycle in which the magnetic poles of the sun reverse. This cycle does affect the amount of solar radiation we receive, but only slightly. But we know that temperatures are currently rising even when the energy received from the sun is reduced – the greenhouse effect, in effect. Greenhouse gases in the atmosphere have in the deep past been effective in ‘releasing’ the planet from ice-bound states.
The Keeling Curve, which has been measuring CO2 in the atmosphere for decades, has it currently at 429.03 ppm, from 315 ppm at its first measurement in 1958, and the increase is accelerating. It’s currently at the highest level for the last million years or so. We know this from measuring bubbles in Antarctic ice cores. Scientists can also distinguish atmospheric CO2 from the burning of fossil fuels, as it has a different chemical signature from naturally occurring CO2. This is rather amazing, and I’m not sure how they know this, but if it identifies the culprit, that’s all to the good. Maybe I’ll write about this in the future, if the chemistry isn’t too complicated.
So I think that’s enough for now….
References
https://en.wikipedia.org/wiki/Climate_change_denial
The Keeling Curve