A casual glance at plots of global mean temperature show something of a hiatus and yet many places are still showing warming. Russia had record heat wave in 2010, the USA in July 2012 and Australia continues to beat records. So what's up with that?
The climate undergoes internal variability in the form of various oscillations like the El Nino Southern Oscillation. During an El Nino, warm waters shift to the central or eastern Pacific and pressures drop there while waters cool in the western Pacific and pressures rise (for the more technically minded, westerly winds in the western Pacific produce waters in the ocean that transport warm water to the east and change the temperature structure of the ocean at and below the surface). During a La Nina, things are the other way around. Normal or neutral years represent a weak La Nina.
El Nino years are more warm globally. The shift of warm seas and lower pressures generates rainfall. As cloud forms, the atmosphere is heated and waves form, effecting weather patterns over north America. Heat is transferred away from the tropics more strongly in the northern hemisphere winter than during its summer. Hence, if the eastern Pacific is cooler than average (La Nina), northern hemisphere winters will be cooler because of the transport of that colder air. This transport of colder air can offset the warming produced by greenhouse gases.
When Kosaka and Xie (Nature, 2013,Published online) looked at global temperatures for 2002 to 2012, they saw that there was cooling during the northern hemisphere winter but warming during the northern hemisphere summer. To finish with a quote:
'All the climate models project a tropical Pacific warming in response to increased greenhouse gas concentrations [that's an increase in El Nino, MP]. We conclude that the recent cooling of the tropical Pacific and hence
the current hiatus are probably due to natural internal variability
rather than a forced response. If so, the hiatus is temporary, and
global warming will return when the tropical Pacific swings back to a
warm state. Similar hiatus events may occur in the future and are
difficult to predict several years in advance owing to the limited
predictability of tropical Pacific SST.'
So this is not good news or an overturning of ideas on climate change, merely the observation that the climate systems is always more complicated than we imagine. The 150+ year old science that burning fossil fuels increase the temperature, stands.
Tuesday, September 3, 2013
Pollution everywhere - keeping pure soundscapes
So I finally got and read Bernie Krause's book, The Great Animal Orchestra. I can highly recommend it. Krause looks at sound in the natural world, both biological and geological. He shows how over the years, changes in the health of the biosphere are visible (or more to the point audible) in the natural soundscape. Selective logging of forests reduces population of bird species. Aircraft sounds can silence the call of animals, making a hole in their aural herding and seeing them eaten.Whales are beached by very loud noises in the oceans, disorienting them. The natural world's soundscape is changed in so many ways.
The sounds of nature are the origins of music, and we seem keyed into some sounds that calm us. As I write I am listening to the sound of the waves, to ease the burden of an open office plan. As an introvert and someone sensitive to external sounds, I felt calmer yesterday and was more productive than when I used Coffivity and its human white noise.
Like pollution that spoils our water, warms our planet or drowns out the night sky with too much life, sound pollution drowns out the natural sounds we developed with. Many people are noise stressed by the sounds of modern life, noisy cars, industry, our digital devices and so on. As we insulate ourselves further from the world around us, it is hard to see how we can preserve it.
One of the fondest noises from my childhood is the warble of magpies and screech of galahs. The sounds of nature have a big place in my life. May there always be places of solitude to listen to the earth and her hymn of praise to the God who made and shapes her.
The sounds of nature are the origins of music, and we seem keyed into some sounds that calm us. As I write I am listening to the sound of the waves, to ease the burden of an open office plan. As an introvert and someone sensitive to external sounds, I felt calmer yesterday and was more productive than when I used Coffivity and its human white noise.
Like pollution that spoils our water, warms our planet or drowns out the night sky with too much life, sound pollution drowns out the natural sounds we developed with. Many people are noise stressed by the sounds of modern life, noisy cars, industry, our digital devices and so on. As we insulate ourselves further from the world around us, it is hard to see how we can preserve it.
One of the fondest noises from my childhood is the warble of magpies and screech of galahs. The sounds of nature have a big place in my life. May there always be places of solitude to listen to the earth and her hymn of praise to the God who made and shapes her.
Wednesday, July 31, 2013
The voice of the natural world
I have this book on order. Can't wait. Are there places we can still go to and be still, listen to creation and give thanks to God for this hymn of praise? Book review to follow.
Thursday, July 11, 2013
Books - print or ebook?
Living in a fully consistent manner is difficult, and as soon as you come out as wanting to be environmentally aware and sustainable you will face criticism. I admit I don't do everything maybe a I should. So when I shared this image recently elsewhere, it wasn't so much the questioning of whether paper is more environmentally sensitive but the 'and you call yourself an environmentalist' statement. C'est la vie. However, a quick web search yielded this article which points out the minimal CO2 cost of download but then the ereaders themselves and the build in obsolescence. Perhaps using a device that has more general uses (like a tablet) will help, but only if you use it for as long as you can rather than chasing the latest novel.
And for myself, yes using libraries saves CO2 and money, and second hand is to be preferred to new when possible, buying local over the faster O/S services. Life is full of difficulties and temptations. That said, let's be encouraging of those who seek to be green and non-aggressive to those who don't
Tuesday, July 9, 2013
Christians & Creation Care: Melbourne meeting Aug 13
We believe God created the world good—and as his children, we have a responsibility to care for creation. A Rocha was founded in Portugal and focuses on environmental education, research and practical environmental action. Although many countries have established A Rocha, it has not yet been launched in Australia.
If care for creation is of interest ‐ please join us on Tuesday August 13 at 7.30pm at St. Judes’ Church in Carlton to discuss the vision for a group representing Christians in conservation in Australia,(potentially an A Rocha chapter) and also consider the weekend of September 28/29 for a weekend of practical environmental action at ‘Watchbox Valley’ (the photo above) an 1160 acre conservation focused farm 90km north on Melbourne in Central Victoria. For more information contact:
Mick Pope (polymath@optusnet.com.au)
Ian Barns (barns.ian.j@gmail.com)
Paul Dettmann (paul@cassinia.com)
Tuesday, July 2, 2013
Vulnerability to climate change
I've been doing the Coursea MOOC Climate Literacy for a few weeks now, it is seemed time to share something of what I've been learning. The basic science has been mostly old for me since I've taught a course on this for some time. However, now we have moved on to impacts I'm starting to pick up on new ideas.
This diagram summarises the ideas behind systems becoming vulnerable to climate change impacts.
Sensitivity is how a system might be at risk to a hazard. Say for example your house is not on stilts. It is therefore sensitive to flooding. However, if you are not near a coast or in a flood plain, then your exposure is low. The product of sensitivity and exposure leads to some risk of potential impacts, in this case of flooding events.
Adaptive capacity is that ability or potential of a system to respond successfully to climate variability and change. In human systems this includes financial coping mechanisms, the role of education and awareness and trust and collaboration in communities. The first factor shows us why the developing world stands to be more vulnerable in many ways than the developed world. Adaptive capacity is a potential in that while we might be able to do something, we might not be willing to do it. Lack of political will is stymieing our ability to avoid a 2 C world!
All of this leads to a systems vulnerability to climate change. Some systems may prove resilient to such changes while others may cross tipping points and collapse.
This diagram summarises the ideas behind systems becoming vulnerable to climate change impacts.
Sensitivity is how a system might be at risk to a hazard. Say for example your house is not on stilts. It is therefore sensitive to flooding. However, if you are not near a coast or in a flood plain, then your exposure is low. The product of sensitivity and exposure leads to some risk of potential impacts, in this case of flooding events.
Adaptive capacity is that ability or potential of a system to respond successfully to climate variability and change. In human systems this includes financial coping mechanisms, the role of education and awareness and trust and collaboration in communities. The first factor shows us why the developing world stands to be more vulnerable in many ways than the developed world. Adaptive capacity is a potential in that while we might be able to do something, we might not be willing to do it. Lack of political will is stymieing our ability to avoid a 2 C world!
All of this leads to a systems vulnerability to climate change. Some systems may prove resilient to such changes while others may cross tipping points and collapse.
Monday, June 17, 2013
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