Do you believe in climate change?

[UK_Palms]

Taking into account your observations when gardening, and specifically growing palms, have you noticed any genuine change in your climate, or evidence of global warming? Or have you become aware through education and through the media?

I'm just wondering what people's thoughts are on here...?

[greysrigging]

Oh oh....'A Climate Change Thread'.... lol
On any other Forum or FB page or even a discussion at the pub, well this topic generally ends in tears, acrimony, insults, lies, propaganda, mis truths, half truths, distortion of facts and figures, and eminent educated scientists squaring off against each other.
Still, for what its worth, it is the Topic of the Century worldwide, and it ain't going away any time soon.
For the record I believe in the concept of Climate Change....and as a bloke who has had a lifelong interest in the weather ( remember here that 'climate' and 'weather are two different things ), a sad individual who actually reads weather stats and has made a hobby of looking at weather records and anomalies, chases storms and drives thousands of kays to insert myself into interesting weather events.
Now I have no technical background in this stuff, merely a keen observer and my observations tell me 'something is up'.....
 Australia wide, there is a significant warming trend of +1c since 1910, and the stats and figures show a steeper upward curve since 1950.
Now the real challenge is to decipher the 'why ?'
Man made ? CO2 emissions, part of a natural cycle of warming and cooling ?
I sorta tune out when that sad schoolgirl is given oxygen by the United Nations.... FFS, for adults who have a passionate agenda, a barrow to push, to descend to manipulating a kid with pre existing mental health issues ( her own parents ! ) well its appalling really.
I also tune out when the Far Right numpties spout their illogical nonsense. Ignorance is not bliss....
As an aside... it is interesting from a social demographic point of view to hear differing opinions on the debate. I'm a member of SKI.COM Forum, a Snow and Weather Forum in Australia that has been around for 20 years, Was also a member of Weatherzone Forums. Some very knowledgeable contributors on both sites. The Ski forums in particular, are very 'Lefty' and one needs to have big cojons to enter into climate change debates on those pages. Quite a few contributors from the 'inner green' suburbs of Sydney and Melbourne.
I respectfully suggest the demographic on our Forum is perhaps older ( if not wiser ) and maybe a bit more sceptical of the intricacies of Climate Change. Fair enough... we should always question things 'eh ?

This is from the BOM State of the climate Report 2018

 

• 
  Australia's climate has warmed just over 1 °C since 1910 leading to an increase in the frequency of extreme heat events.
• Oceans around Australia have warmed by around 1 °C since 1910, contributing to longer and more frequent marine heatwaves.
• Sea levels are rising around Australia, increasing the risk of inundation.
• The oceans around Australia are acidifying (the pH is decreasing).
• April to October rainfall has decreased in the southwest of Australia. Across the same region May–July rainfall has seen the largest decrease, by around 20 per cent since 1970.
• There has been a decline of around 11 per cent in April–October rainfall in the southeast of Australia since the late 1990s.
• Rainfall has increased across parts of northern Australia since the 1970s.
• Streamflow has decreased across southern Australia. Streamflow has increased in northern Australia where rainfall has increased.
• There has been a long-term increase in extreme fire weather, and in the length of the fire season, across large parts of Australia.

 

 

Global

• Concentrations of all the major long-lived greenhouse gases in the atmosphere continue to increase, with carbon dioxide (CO 2) concentrations rising above 400 ppm since 2016 and the CO 2 equivalent (CO 2-e) of all gases reaching 500 ppm for the first time in at least 800,000 years.
• Emissions from fossil fuels continue to increase and are the main contributor to the observed growth in atmospheric CO2.
• The world’s oceans, especially in the southern hemisphere, are taking up more than 90 per cent of the extra energy stored by the planet as a result of enhanced greenhouse gas concentrations.
• Global sea level has risen by over 20 cm since 1880, and the rate has been accelerating in recent decades.
• Globally averaged air temperature has warmed by over 1 °C since records began in 1850, and each of the last four decades has been warmer than the previous one.

Future
Australia is projected to experience:

• Further increases in sea and air temperatures, with more hot days and marine heatwaves, and fewer cool extremes.
• Further sea level rise and ocean acidification.
• Decreases in rainfall across southern Australia with more time in drought, but an increase in intense heavy rainfall throughout Australia.

 

 

 

[greysrigging]

Some more light reading......

Australia's changing climate
Temperature
Australia's weather and climate are changing in response to a warming global climate. Australia has warmed just over 1 °C since 1910, with most warming since 1950. This warming has seen an increase in the frequency of extreme heat events and increased the severity of drought conditions during periods of below-average rainfall. Eight of Australia’s top ten warmest years on record have occurred since 2005.
The year-to-year changes in Australia’s climate are mostly associated with natural climate variability such as El Niño and La Niña in the tropical Pacific Ocean and phases of the Indian Ocean Dipole in the Indian Ocean. This natural variability now occurs on top of the warming trend, which can modify the impact of these natural drivers on the Australian climate.

Anomalies in annual temperature over land in the Australian region. Anomalies are the departures from the 1961–1990 standard averaging period.
Increases in temperature are observed across Australia in all seasons with both day and night-time temperatures showing warming. The shift to a warmer climate in Australia is accompanied by more extreme daily heat events. Record-warm monthly and seasonal temperatures have been observed in recent years, made more likely by climate change.
Examining the shift in the distributions of monthly day and night-time temperature shows that very high monthly maximum temperatures that occurred around 2 per cent of the time in the past (1951–1980) now occur around 12 per cent of the time (2003–2017). Very warm monthly minimum, or night-time, temperatures that occurred around 2 per cent of the time in the past (1951–1980) now also occur around 12 per cent of the time (2003–2017). This upward shift in the distributions of temperature has occurred across all seasons, with the largest change in spring.

Number of days each year where the Australian area-averaged daily mean temperature is extreme. Extreme days are those above the 99th percentile of each month from the years 1910–2017. These extreme daily events typically occur over a large area, with generally more than 40 per cent of Australia experiencing temperatures in the warmest 10 per cent for that month.
Key points

• Australia’s climate has warmed by just over 1 °C since 1910, leading to an increase in the frequency of extreme heat events.

Fire weather
Fire weather is largely monitored in Australia using the Forest Fire Danger Index (FFDI). This index estimates the fire danger on a given day based on observations of temperature, rainfall, humidity and wind speed. The annual 90th percentile of daily FFDI (i.e., the most extreme 10 per cent of fire weather days) has increased in recent decades across many regions of Australia, especially in southern and eastern Australia. There has been an associated increase in the length of the fire weather season. Climate change, including increasing temperatures, is contributing to these changes. Considerable year‑to‑year variability also occurs, with La Niña years, for example 2010–2011 and 1999–2000, generally associated with a lower number of days with high FFDI values.

Trends from 1978 to 2017 in the annual (July to June) sum of the daily Forest Fire Danger Index—an indicator of the severity of fire weather conditions. Positive trends, shown in the yellow to red colours, are indicative of an increasing length and intensity of the fire weather season. A trend of 300 FFDI points per decade is equivalent to an average trend of 30 FFDI points per year. Areas where there are sparse data coverage such as central parts of Western Australia are faded.

Area average of the number of days with FFDI greater than 25 (very high fire danger) in Victoria in spring for the years starting in July (1978–2017). Although there is considerable interannual variability in the index, there is also a clear trend in more recent decades towards a greater number of very high fire weather days in spring.
Key points

• There has been a long-term increase in extreme fire weather and in the length of the fire season across large parts of Australia since the 1950s.

Rainfall
Australian rainfall is highly variable and is strongly influenced by phenomena such as El Niño, La Niña, and the Indian Ocean Dipole. Despite this large natural variability, underlying long-term trends are evident in some regions. There has been a shift towards drier conditions across southwestern and southeastern Australia during April to October. Northern Australia has been wetter across all seasons, but especially in the northwest during the tropical wet season.
Year-to-year variability occurs against the background drying trend across much of the southern half of Australia (south of 26° S). In 17 of the last 20 April to October periods since 1999, southern Australia has had below average rainfall. Recent years with above-average rainfall in this region were generally associated with drivers of higher than usual rainfall across Australia, such as a strong negative Indian Ocean Dipole in 2016, and La Niña in 2010.

April to October rainfall deciles for the last 20 years (1999–2018). A decile map shows where rainfall is above average, average or below average for the recent period, in comparison with the entire rainfall record from 1900. Areas across northern and central Australia that receive less than 40 per cent of their annual rainfall during April to October have been faded.
Key points

• April to October rainfall across southeastern and southwestern Australia has declined.
• Rainfall has increased across parts of northern Australia since the 1970s.

 

Anomalies of April to October rainfall for southwestern (southwest of the line joining the points 30° S, 115° E and 35° S, 120° E) and southeastern (south of 33° S, east of 135° E inclusive) Australia. Anomalies are calculated with respect to 1961 to 1990 averages.
The drying in recent decades across southern Australia is the most sustained large-scale change in rainfall since national records began in 1900. The drying trend has been most evident in the southwestern and southeastern corners of the country. The drying trend is particularly strong between May to July over southwest Western Australia, with rainfall since 1970 around 20 per cent less than the average from 1900 to 1969. Since 1999, this reduction has increased to around 26 per cent. For the southeast of the continent, April to October rainfall for the period 1999 to 2018 has decreased by around 11 per cent when compared to the 1900 to 1998 period. This period encompasses the Millennium Drought, which saw low annual rainfall totals across the region from 1997 to 2010.
This decrease, at an agriculturally and hydrologically important time of the year, is linked with a trend towards higher mean sea level pressure in the region and a shift in large-scale weather patterns—more highs and fewer lows. This increase in mean sea level pressure across southern latitudes is a known response to global warming. There has been a reduction in the number of cold fronts impacting the southwest, and a decrease in the incidence and intensity of weather systems known as cut-off lows in the southeast regions of Australia. Cut-off lows bring the majority of rainfall and the most intense rainfalls in some regions of eastern Victoria and Tasmania.

Northern wet season (October–April) rainfall deciles for the last 20 years (1998–99 to 2017–18). A decile map shows where rainfall is above average, average or below average for the recent period, in comparison with the entire national rainfall record from 1900.

Anomalies of October to April rainfall for northern Australia (north of 26° S inclusive). Anomalies are calculated with respect to the 1961 to 1990 average.
Heavy rainfall
Although the range of natural variability in heavy rainfall is very large, there is evidence from observed weather station records that a higher proportion of total annual rainfall in recent decades has come from heavy rain days.
As the climate warms, heavy rainfall is expected to become more intense, based on the physical relationship between temperature and the water-holding capacity of the atmosphere. For heavy rain days, total rainfall is expected to increase by around 7 per cent per degree of warming. For short‑duration, hourly, extreme rainfall events, observations in Australia generally show a larger than 7 per cent increase. Short-duration rain extremes are often associated with flash flooding.
Key points

• There is evidence that some rainfall extremes are becoming more intense.

Streamflow
The observed long-term reduction in rainfall across southern Australia has led to even greater reductions in streamflows. For example, the mean annual streamflow into Perth water storages has dropped from 338 GL during the period 1911–1974 to 134 GL during the subsequent years from 1975–2017. During this latter period there is a continuing decline to a mean annual inflow of 47 GL during the last six years.
Declines in streamflow have also been observed in four drainage divisions: the Murray–Darling Basin, South East Coast (Victoria) and South East Coast (New South Wales) (which include Sydney and Melbourne), and the South Australian Gulf (which includes Adelaide). In each of these drainage divisions between two thirds and three quarters of streamflow records show a declining trend since the 1970s.
In the Tanami–Timor Sea Coast drainage division in Northern Australia, which includes Darwin and covers much of the Northern Territory, there is an increasing trend in mean annual flows at more than half of the gauging stations, following an increase in rainfall since the 1970s.
Key points

• Streamflow has decreased across southern Australia since the 1970s.
• Streamflow has increased in northern Australia, since the 1970s, in places where rainfall has increased.

Tropical cyclones
Tropical cyclone activity in the Australian region, which is specified as the ocean and land areas from 90° E to 160° E in the southern hemisphere, has large variability from year-to-year, due to the influence of naturally occurring climate drivers. For example, the number of tropical cyclones in the Australian region generally declines with El Niño and increases with La Niña.
Observations since 1982 indicate a downward trend in the number of tropical cyclones in the Australian region.
In contrast to the number of tropical cyclones, cyclone intensity is harder to observe, so it is not currently possible to quantify any trends with a substantial degree of confidence.
Key points

• There has been a decrease in the number of tropical cyclones observed in the Australian region since 1982.

Snow
Downward trends in snow depth have been observed for Australian alpine regions since the late 1950s, with largest declines observed during spring. Downward trends in the spatial extent of snow cover in Australia have also been observed. Snow depth is closely related to maximum temperatures, and the observed declines are associated with the long term trend of increasing temperatures.
Key points

• A downward trend in snow depth has been widely observed for Australian alpine regions since the late 1950s.

Compound events
While scientists often report on changes in individual climate variables, such as rainfall, historically significant weather and climate events are often the result of the combined influence of extremes in multiple variables occurring simultaneously. These events are commonly the most impactful and hazardous, and planning for such events is a major component of disaster risk reduction and resilience.
Compound extreme events can occur in various ways. This includes an extreme storm surge, combined with extreme rainfall, leading to extreme coastal inundation. Similarly, extreme rainfall and extreme high wind events along the New South Wales coast are often associated with the simultaneous occurrence of an intense low pressure system, cold front and thunderstorms.
Compound extreme events can also describe the confluence of climate and weather extremes of varying timescales, such as a drought period intersecting with a prolonged heatwave, or record high daily temperatures—an occurrence which typically results in large impacts on agriculture, human health, fire weather and infrastructure.
Climate change can have a significant influence on the frequency, magnitude and impact of some types of compound events.
For example, the confluence of background warming trends, background drying trends and natural variability saw extreme heat and low rainfall across Tasmania during the spring, summer and autumn of 2015–2016. October 2015 saw the third highest mean monthly maximum temperature on record for the State, record low monthly rainfall and record high fire danger. These conditions rapidly transitioned to record atmospheric moisture and heavy rainfall in June. Tasmania experienced significant impacts from these events, including drought and fires, followed by flooding.
There is also a trend in some regions towards an increasing number of days when high fire danger ratings are combined with conditions that allow bushfires to generate thunderstorms. This can lead to extremely dangerous fire conditions as observed for the Canberra (2003) and Black Saturday (2009) fires, including generating additional fires from lightning strikes.
As climate change continues, the combination of increases in heavy rainfall and rising sea levels means that coastal and estuarine environments may have an increase in flood risk from multiple causes.
Projecting the occurrence and severity of future compound extreme events is a significant scientific challenge, as well as a very important one for future climate adaptation.

[PALM MOD]

I "believe" and agree that

On any other Forum or FB page or even a discussion at the pub, well this topic generally ends in tears, acrimony, insults, lies, propaganda, mis truths, half truths, distortion of facts and figures, and eminent educated scientists squaring off against each other.

but I'm willing to give it another try. But no political, religious, controversial, or antagonist comments or this topic will disappear.

[greysrigging]

^^And so it should.... play nice and stick to the 'facts'.... oh and play the ball, not the man, to use a sporting vernacular ....

[sandgroper]

I believe the climate is changing but also believe that while we may well be contributing to it that it is mostly a natural occurrence. I was a safari tour guide in the north west of Western Australia for 9 years and visited Kalbarri National Park weekly during that time. The Murchison River flows through the area where scientists say the sandstone rock formations are 430 million years old, the rocks are made up alternately of red rock and white rock which form uniform lines right through the area. Geologists say this shows where at certain times the ocean levels were higher washing white sand in from the sea and at other times the sea level was lower and red sediment was washed out from the surrounding desert, all of this has turned to stone over millennia. If this is true then it was certainly happening long before man walked the earth. Anyway, this what I was told by people who know about these things and what I personally believe - doesn't mean I'm right or wrong, it's just my belief.

[mdsonofthesouth]

6 hours ago, greysrigging said:

^^And so it should.... play nice and stick to the 'facts'.... oh and play the ball, not the man, to use a sporting vernacular ....

Problem is some folk's, not pointing any fingers here, use the wrong facts or misuse an experiment to prove a point or even swear up and down that their mis information is relevant to this discussion and is set in stone. Science isn't ever set in stone. Again not pointing fingers just pointing out why this discussion rarely goes well. Point I'm trying to make is people never play nice on this topic. Again not pointing fingers, just merely stating an observation from past discussions. 

 

That aside I believe climate changes in a cyclical way here on earth whether we humans like it or not...or are even here or not. We have a complex where we think we are more important and impactual than we really are to this earth(and almost everything), and while we do have an ever so slight effect it is mostly vanity. The world will change despite what we do and it will go through warming and cooling periods with or without us.

 

Do I think we can do better? Sure! But it's pur vanity to think we caused this...

 

Edited December 2, 2019 by mdsonofthesouth

[Fusca]

We must also be careful when making predictions for the future.  As a statistician I know that valid use of predictive modeling cannot be based on too many assumptions.  Predictions are valid only for the range of data used to estimate the model.  The relationship between the independent variables and the dependent variable can change outside of that range.  We don't know whether the shape of the curve changes and if it does change our predictions will be invalid.  When did recording of "official temperatures" start?

[greysrigging]

15 hours ago, Fusca said:

We must also be careful when making predictions for the future.  As a statistician I know that valid use of predictive modeling cannot be based on too many assumptions.  Predictions are valid only for the range of data used to estimate the model.  The relationship between the independent variables and the dependent variable can change outside of that range.  We don't know whether the shape of the curve changes and if it does change our predictions will be invalid.  When did recording of "official temperatures" start?

Using Australia as an example, the standard measuring platform is known as a Stevenson Screen. these came into general use by the Bureau of Meteorology between 1908 and 1913, although the larger cities ( ie Capitals of our States and Territories ) had them from about the 1870's.
Our State and Federal records generally date from 1910, recordings prior to 1910 in rural and country regions without Stevenson Screens are regarded as 'suss' as non standard instrumentation was in general use.



 

[cbmnz]

I've been a fence sitter on the subject for a long time, given the fact that CO2 is such a tiny part of the atmosphere, it relies on "amplification" by water vapour which is the dominant greenhouse agent. And even with that, there is consensus that without further positive feedbacks, a literal doubling of CO2 would only lift global temperatures by 1.5 to 2C max. 

If the experts think they have accounted for all known factors and their work is telling them there is a high chance of seeing 4-6C rise (which would be really nasty/catastopic) if we double CO2, then I'm prepared to take their word for it, but at the same time knowing that it's a big leap they are making. They should understand that extraordinary claims require extraordinary evidence however.

Up until 2017, locally there had been no noticeable change in the climate.  But since then do seem to be seeing some effects. Have had three mild winters in a row now, and 2 hot summers, and this one has started with a roar in  November with temperatures of up to 30C in the first week and again in the last. If this carries on does three milder than usual winters and 3 warmer than usual summers in a row mean climate change is real or is this just a short term excursion?

This year a number of places within 200km are on about 700mm YTD rainfall with only 4weeks left in the year, when long term average rain is 1150mm or so.

Anyway, for now as a gardener it's great as it's lifted my area into a very solid 9B with summer heat. Can grow R. Baueri as well as Sapida, A cunninghamiana and A. Maxima are flourishing getting very tall and flowering everywhere, Avocados are fruiting in people's backyards. Bananas are survivng the winter unprotected with quite a few green leaves.  My grapevine is fully ripening a second crop by May from flowers off the lateral buds. The same vine from 2003-2017 the second crop grapes always got to the  large and green state but did not ripen before it turned cold in June and they rotted away.   Be nice if it could stay this way, but this is plenty, don't need anymore warming or any further reduction in rainfall.

Appreciate that for areas that were already warm/dry and have always  faced wildfire danger this change already occurred has created hardship though, it was not needed. 

 

 

 

 

 

Edited December 3, 2019 by cbmnz

[Walt]

Do I believe in climate change? Of course, what else would explain the past five major ice ages and intervening greenhouse periods -- the last ice age ending 11,700 years ago when early man's impact on the climate was about a strong as a fart in a hurricane. 

Do I think that current climate change is man made? Surely, man is contributing to it. To say otherwise is pure ignorance and/or delusion IMO.  Man is at the very least contributing to atmospheric pollution. That's just a fact.

But my opinion is that the biggest factors of climate change are factors beyond man's control. Would I like to see man pollute less, absolutely. Do I think,  on a world-wide scale, man will significantly reduce the amount of atmospheric pollution that CC/GW alarmists think levels should be reduced to? No, I don't. Man is going to do what he wants to do as he has done since time immemorial. Man (in all countries on earth) will continue to scratch and claw for everything they can get ,and if that means generating more pollution, so be it. It's the nature of man.

 

[GottmitAlex]

Bottom line is: We have 11 years before cataclysmic events cannot be stopped, much less reversed by man.

https://www.bbc.co.uk/news/science-environment-45775309

http://rex.b92.net/en/Recommendations/story/6421/Final+call+to+save+the+world+from+'climate+catastrophe'.html

 

Edited December 3, 2019 by GottmitAlex

[Jubaea_James760]

In my opinion it's just another reason to extort money from us. They tell us we need to stop eating burgers & trade in our gas guzzlers for electric car or else! While the biggest pushers already have stocks & invested in this "new world" they want to create. The earth is going to do what the earth is going to do regardless of humans. There's no possible way they could know the date and time of global catastrophes to increase because of our co2 emissions. If this earth has been existant for "millions of years", which they claim & we have only kept records of weather a little over a 100 years it seems pretty unlikely we know humans are causing earth's destruction in my opinion. 

We cant think that global catastrophes are unique to our time.Wild fires, earthquakes, floods, hurricanes, global warming/cooling etc..  there's nothing new under the sun on this earth. 

[Walt]

6 hours ago, James760 said:

In my opinion it's just another reason to extort money from us. They tell us we need to stop eating burgers & trade in our gas guzzlers for electric car or else! While the biggest pushers already have stocks & invested in this "new world" they want to create. The earth is going to do what the earth is going to do regardless of humans. There's no possible way they could know the date and time of global catastrophes to increase because of our co2 emissions. If this earth has been existant for "millions of years", which they claim & we have only kept records of weather a little over a 100 years it seems pretty unlikely we know humans are causing earth's destruction in my opinion. 

We cant think that global catastrophes are unique to our time.Wild fires, earthquakes, floods, hurricanes, global warming/cooling etc..  there's nothing new under the sun on this earth. 

My friend, you are introducing sound logic into the CC argument. That conflicts with many folks's self-serving and pontificating opinions and feelings (but not mine) on just when the beginning of the end will start.

My position: I am a firm believer (based on geological and other physical evidence) that the earth has gone through many cycles of climate change -- none of which were caused by man, as man hadn't evolved yet. As you stated, wild fires, earthquakes, floods, hurricanes (and I will add volcanoes and major meteor impacts) can trigger climate change. Just how much a factor the aforementioned factors were is anybody's guess. Climate change happens in spite of man -- but man (with all the pollution that he generates today) surely can exacerbate and influence and speed up natural causes. IMO, to believe man has no impact at all on the earth's climate is utter nonsense. 

If I'm lucky I may have 20 years of life left on this earth. I'm willing to make some sacrifices in my energy use,driving habits, etc. that contributes to higher atmosphere CO2, and I'm willing to cut back my use of plastics and other materials that pollute our ground water and oceans, etc. But I'm not willing for the US to take an inordinate big hit in its economy and lifestyle while other countries are given a pass for 10 more years (as per the Paris Agreement to be able to build more coal fired power plants, etc.) and not make equal sacrifices. 

I believe man, due to his ever growing technology, will eventually destroy himself, or at least to  the point that life on earth will be a living hell. So man perishing due to climate change doesn't really concern me. Man is going to perish one way or the other, and I believe by his own hand.

 

[HtownPalms]

This is a very interesting topic. Do I believe in climate change? Yes. Do I believe it is caused entirely by man? No. As stated earlier I believe it is a natural cycle, although I do believe man could be speeding its affects. There is significant evidence showing that the global temperatures were warmer in the past and colder in the past. In the future this cycle will continue. I would love to see mans impact on the environment reduced whether I believed in climate change or not. I try to limit my impact on the environment as much as reasonably possible. I'm not an environmentalist, but I probably do more than most people do to limit my impact. I'm never going to go Greta Thurnburg on society, but if people are flat out being negligent about their impact be it a country, company, or individual then I do believe action should be taken. I also agree that there is a small part of the population that is whipping up hysteria about this for personal gain without a real care for what they are espousing. 

[GottmitAlex]

 

[PALM MOD]

As anticipated, this discussion inevitably strays into the political arena. When Al Gore, the Obama Administration, and government in general enter the discussion (in the video), politics have been introduced.

However, this time I will not delete the topic since the tone has stayed polite. But I will be locking it since I'm guessing that if I didn't it would only become more political.