Climate Spiral [video] | Hacker News Reader

Climate Spiral [video]

svs.gsfc.nasa.gov

133 pointsYashdharaC83 comments

Loved this 'climate spiral' designed by Prof. Ed Hawkins at Univ. Reading. The visualization presents monthly global temperature anomalies between the years 1880-2021. Data came from the Goddard Institute of Space Studies (GISS), a NASA laboratory.

I really like this one as well: https://svs.gsfc.nasa.gov/4978

Wow. Really doesn’t paint a happy picture for the northern hemisphere

Industrialization happened first and most in the northern hemisphere, so it makes sense that there’s a larger co2 warming effect.

It is important to show that the warming and anomalies are uneven, because in the north (specially over the northern polar circle) a few positive feedback loops happen, like permafrost thawing that emits CO2 and methane that were frozen there for very long time.

I'm not sure that that reinforcement of the trends were taken into account in old models, or how much it can accelerate things over old predictions that may still be used to dictate policies.

so here's a fun question: it's become quite trendy in policy circles in california to incentivize the removal of lawns and gardens as part of water conservation efforts.

doesn't removal of fertile topsoil and replacement of it with rocks and cacti at scale actually reduce carbon sequestration and heat absorption capacity?

The water conservation need outweighs the marginal carbon sequestration I’d imagine.

What was the vegetation like before humans arrived? We should go back to that.

Grassy lawns and lush gardens in dry areas require so much water any water any possible benefit of carbon sequestration is counterbalanced by the irrigation infrastructure required.

Do cashew farms and strawberries next

As far as I know almonds are a major water-guzzler of Californian crops, no?

Yep

Here's some stats

https://www.pressdemocrat.com/article/specialsections/these-...

I don't think so in any meaningful way. Also, removing and wasting the water to keep a lawn green heats the river that water was pulled from.

Plus, mowing a lawn is usually done with some of the dirtiest engines out there.

Removing lawns is always a net good.

sure, but don't we put lawns on roofs in cities to try and cool them down in the summer?

i understand the notion of returning to existing vegetation, but these places are already irreversibly altered by the presence of humans anyway. buildings and parking lots and roads and sidewalks have been built.

it's pretty striking when you see what little soil remains being replaced with rocks.

Rooftop lawns in cities are to offset the increase in heat generated by having the city there. They are an attempt to return the environment to something closer to natural.

And yes, xeriscaping is striking. Absolutely beautiful to see native plants, well adapted to the climate, thriving and taking center stage.

In many places green roofs are primarily about reducing rainwater runoff, which causes pollution. However in hot areas like LA, they also reduce building temperatures which reduces energy consumption. Lawns don't reduce building temperatures.

In addition, I wonder what effect this sort of “manual desertification” has on the soil when done en masse.

It seems odd to me to frame this as manual desertification. Isn't it the opposite, return to a natural state after manual "grassification" that requires strong human intervention?

It's not an environment that naturally supports soil. The energy and water needs to support an unnatural environment are quite large.

[EDIT: Below I have demonstrated a slow brain rot that has robbed me of my ability to do basic dimensional analysis. My lecturers are spinning in their graves, least of all because I forgot that the kilogram is between the gram and the tonne. Luckily I was off by 3 orders of magnitude in both directions so I guess it sort of balances out?]

The heat absorption is a good point, I don't know what native foliage is like to live in compared to the concrete hell you'd be left with without lawns. But, I find it hard to imagine that turf grass in climates where it can't survive without massive irrigation and ceaseless human intervention sequesters more carbon than it costs to maintain.

The numbers I've quickly gathered are all over the place, but given that:

- The average Californian lawn is ~500 sqm [0]

- Grass sequesters ~ 85g of carbon per sqm per year, or 42 tonnes per year [1]

- As of 2011 the average Californian household uses 190 gallons of potable water a day on landscaping [2]

- About 0.004 metric tonnes of carbon is generated processing 1000 gallons of potable water or 0.76 tonnes per day of watering [3]

So, the average Californian lawn sequesters 42 tonnes of carbon a year, while the energy cost of irrigating it emits about 277 tonnes.

This is all quick back of an envelope math, but the carbon cost of irrigating a lawn where it wasn't meant to grow is massively larger than the amount that the grass sequesters. It's honestly bad enough that you could tear up every lawn in California and not even bother replacing them with native foliage, and it would still result in a net decrease in carbon emissions.

[0]: https://www.homeadvisor.com/r/average-yard-size-by-state/

[1]: https://www.researchgate.net/publication/282543110_Modeling_...

[2]: https://www.kqed.org/lowdown/11525/how-much-water-do-califor...

[3]: http://leansixsigmaenvironment.org/index.php/how-much-impact...

> - The average Californian lawn is ~500 sqm [0]

> - Grass sequesters ~ 85g of carbon per sqm per year, or 42 tonnes per year [1]

500 * 85g/m2 = 42500 g/m2 - that's 42.5 kg, not 42.5 tonnes.

I haven't checked your original sources, but based on the numbers you provided you're off by 3 orders of magnitude. Intuitively this makes sense, I mean 42 tonnes is a huge amount of carbon to sequester in a lawn. Where would all that mass go? It would mean that the average lawn produces >> 42 tonnes of grass per year.

You're completely right that was a misstep, I was thinking that seemed high but didn't really think it through - that would be a ludicrous mass of trimmings... So the sequestration is even lower.

Imagining 42 tons of yard waste piling up outside every year, seems a little off the mark.

500 sqm X 85 g/yr is 42.5 kg/yr

Also, 190 gpd / 1000 gal = 0.19 kgal per day

0.004 tons per kgal per day x 0.19 x 365 days = .277 tons per year

Therefore 0.0425 tons sequestered, 0.277 tons produced by irrigation.

The ratio of carbon sequestered to carbon produced on irrigation is the same as your original calculations.

But I think the major source of carbon won't be in irrigation, but in the maintenance, mowing the lawn, transportation for the landscaper, transporting pesticides and fertilizers, etc.

[3] seems like a bit of a stretch to me. we know for a fact that different communities have different energy needs for moving water around based on simple geography. we also know that different communities have different electricity sources providing municipal power. (the bay area's primary water system makes use of hydroelectric power, for example). finally, i'm not convinced that the marginal cost per gallon makes up the total cost of moving water around. much of the costs are fixed infrastructure costs that don't necessarily move with utilization.

here's a thought experiment: assume infinite clean electricity and desalination capacity in the face of an overcarbonated atmosphere and climate change. do you install and irrigate as much vegetation as you can or do you rip it all out and put in rocks?

Most of LA would be a rocky semi-desert without irrigation. If you want to sequester carbon, maybe do it someplace that does have rainfall to support an effective carbon-sink ecosystem and doesn't require huge amounts of energy input?

I wonder if there’s some vegetation that could be watered with seawater and take the place of grass? Places like LA have plenty of that, seemingly.

Lawn is net zero if you ignore all secondary emissions because the grass will be cut and decompose into methane. When the many secondary emissions are considered it's certainly emitting more carbon than it capture. But it improve the micro-climate of the city and possibly reduce AC usage.

This visualisation is misleading because the visual area covered increases quadratically as the radius increases, and (less misleading) the velocity of the 'pen' increases linearly too. But it's measuring a difference (not an absolute quantity): so velocity and (especially) area are arbitrary. I could take the same graph and apply it to the period between 1890 and 1945 and it would seem just as concerning, with a different scale.

The change of color also and the fact that it’s temperature anomalies, not average temperature.

I wonder what is actually behind ’temperature anomalies’, what does it mean, how is it calculated?

https://en.wikipedia.org/wiki/Temperature_anomaly

As I understand it, this is a more useful number when trying to measure changes of average temperature over time.

Ok, I found the answer: it’s supposed to be the average of the difference of temperature over close to a million of region on the earth.

Here's the data source, which includes links out to papers on how the data is collected and calculated.

https://data.giss.nasa.gov/gistemp/

It could be misleading the other way too, if the starting radius was extremely large and the increments very small, then it could be made to look like no big deal. But that's the thing with temperature. We rarely start graphs at absolute zero (-273C), so what's your point again?

My point is if you want to inform people about climate changes, be accurate with visualisations (i.e. don't equate something quadratic with something linear without being very transparent about this). If you want it to not be arbitrary, put some context with the numbers/scale.

Like maybe plot temperature changes vs CO2 over time on a linear scale, and compare with changes that led to previous ice ages on that same scale. Or something of this vein.

In what way are you trying to interpret the area, or indeed the velocity (indeed the angular velocity is constant)? As I understand it, the intent of the visualisation is simply to make clear the temperature (anomaly) trend, which is encoded in the radius - that is all you need to consider to understand what is being shown.

Also, the fact that it uses anomalies isn't of much consequence, given that there is widespread understanding of "normal" temperatures, to which the anomalies can be compared - this is unlike many situations where readers might not have an understanding of usual absolute values, making the plotting of differences prone to being misleading. According to [0] the anomaly difference for 1890-1945 is 0.44 K, whereas for 1880-2021 it is 1.01 K, so presumably someone who was concerned by the former would be (approximately) doubly concerned by the latter.

[0] https://climate.nasa.gov/vital-signs/global-temperature/

Angular velocity is not velocity, the velocity increases because the angular velocity was remaining constant as the radius increased.

It's encoded in the radius, but the area is visually more impactful - to me anyway - until the end when it's shown from the side, which was good.

The point about comparing up to 1945 is that since the scale is arbitrary I can have it end at the same radius.

I didn't suggest that angular velocity is the same as linear velocity, I asked how you were interpreting the area and velocity, and parenthetically observed that the angular velocity was constant. You say that the area is impactful - what do you understand it as meaning?

The scale is not arbitrary, it covers the range of anomalies over the chosen period, in units of temperature change in degrees Celsius, and is labelled as such, with the anomaly reference period described in the text. If you were to use absolute values then the scale would similarly cover the range of absolute values over the chosen period - there is no "unbiased" choice of data range, except perhaps that which covers all of the data in question, which this does.

As I noted, the impact of the anomalies is with reference to "normal" temperatures - it is relatively easy for anyone to see that 1 C (/K) is quite a large temperature increase, relative to "normal" temperatures. Surely you can agree that if the largest anomaly shown was 0.01 C then the graph would have far less impact, and if it was 100 C then the graph would have far more impact?

>I didn't suggest that angular velocity is the same as linear velocity, I asked how you were interpreting the area and velocity, and parenthetically observed that the angular velocity was constant.

If you make tangential observations the conversation may move tangentially.

>You say that the area is impactful - what do you understand it as meaning?

It's a visualisation, i.e. the visuals are meant to contain the meaning, and said visuals are important and need to be carefully considered. Areas of 2D shapes tend to represent some kind of quantity, where the area is proportional to the quantity (and if the area was quadratically related to the quantity that would be misleading or inaccurate).

>Surely you can agree that if the largest anomaly shown was 0.01 C then the graph would have far less impact, and if it was 100 C then the graph would have far more impact?

The point is about the meaning of the choice of visualisation and the choice of data and context provided. That's why I compare with 0.01C, because to the layman 2C and 0.01C are both not significant, but the actual environmental impact of the 2C could be very much more significant with more context. You don't need to be very informed to know 100C is significant.

> If you make tangential observations the conversation may move tangentially.

You (presumably) have agency, and could have chosen to answer the main question rather than labouring your misconstrual of the parenthetical.

> Areas of 2D shapes tend to represent some kind of quantity ...

They sometimes represent some kind of quantity, but here they don't, and despite my repeatedly asking you have been unable to provide any interpretation of what that quantity might mean. Lots of other people seem to be able to understand the graph just fine - perhaps you simply dislike the popularly stated inferences and are looking for holes to pick?

To be honest, for a problem that's only been around for 50 years and that requires major technological and economic disruption combined with global geopolitical cooperation to solve, I'd say we, as a species are doing pretty good at coming together to combat climate change.

Is it easy to imagine going faster, easily. Are we doing absolutely everything we can, assuredly not. Is there still going to be dramatic ecological fallout, definitely. But still... humanity's historical track record for these kinds of changes is on the order of centuries or millennia, not decades.

On the other hand we never had so much knowledge.

Your comment reads as an excuse in why it's okay that we are that slow.

Very cool visualization! What are the causes of the rapid acceleration starting in the 80s, I assume globalization had something to do with it?

Climate effects are typically delayed by decades.

The post war era saw a huge jump in resource usage, and the discovery of the Haber process resulted in huge agricultural returns, enabling a massive population spike.

The post war era led to the massive population spike, not improved farming. Anyone apart from their honey for more than a week knows that.

It's not so simple. Haber's process increased the population the globe could support by billions. So yes, baby boomers came from post war era, but global availability of food meant that the generations following didn't starve or cap out.

Probably what sibling comment said, and the economic boom after WW2.

This op-ed[1][2] says:

> For a few years, I’ve startled people by pointing out that over half of all of the emissions from the burning of fossil fuels that have ever been produced in the history of humanity have been produced in the past 30 years — since Al Gore published his first book on warming; since the U.N. established its climate-change body, the I.P.C.C.; since the premiere of “Friends.”

Which is fucking shocking. Later on he says "At the Rio Earth Summit in 1992, the global promise was to avoid “dangerous” warming.", if I were the editor I'd point out that's 30 years ago and that he should add something like "the cutoff-year after which we've emitted in 30 years the same amount of fossil fuel emissions of the last several millennia until that point".

Obviously this is "citation needed" territory, but I'm relying on the reputation of NYT to have hired a researcher that backs up what he's written with hard data.

[1] https://www.nytimes.com/2022/05/17/opinion/india-heat-wave-p... [2] https://archive.ph/GTtXP

Well, the Keeling Curve (the record of CO2 accumulation in the atmosphere since the late 1950s) shows pretty steady accumulation, though it's not quite a linear line, it's slightly exponential.

https://climate.nasa.gov/vital-signs/global-temperature/

If you compare that to the global temperature data presented in the same kind of graph, there's this relatively flat period from the 1950s through the 1970s, before the steady climb begins:

https://climate.nasa.gov/vital-signs/global-temperature/

CO2 is best understood as having its most potent effect at about ~12 km up in the atmosphere, this is where under pre-industrial conditions there was a large 'escape window' for infrared radiation (due to colder temps and lower pressures). That warming in turn drives water vapor feedback at lower levels in the atmosphere, with the water vapor accounting for 2/3 or so of the actual radiative trapping and the CO2 accounting for about 1/3 (then there's methane, a compounding factor but IIRC it's about 1/20th overall).

If we take the Milankovitch cycle of glacial ages into account, the world without fossil CO2 should have been steadily sliding into another ice age (with the warm peak about 10K years ago). So the flattening out period represents perhaps the end of that trend (driven by orbital parameters, and associated feedbacks w/ ice sheets and CO2).

Now the CO2, thanks to steady increase, is the dominant factor controlling global temperature trends, and the global temperature is basically just tracking the global atmospheric CO2, with a lag time of at least several decades (I think it's more like 100 years for the global temperature to catch up with the global atmospheric CO2, but that's a matter of debate).

Conclusion: even if we take dramatic action to curb fossil fuel use (which is a good idea), we're going to be stuck with a steadily rising global temperature for at least 100 years before leveling off (and this ignores issues like permafrost outgassing of additional CO2 and methane destabilization in shallow marine sediments). Hence humans are going to have to plan for adaptation to these new climatic conditions. The point has been well tipped, and we're in for it.

The reason for the acceleration is because most of the greeh house gas emissions (CO2, CH4 etc) once emitted will stay in the atmosphere for a very long time (100s of years, they accumulate). PLus we are emitting these at a much faster pace than they can be removed from the atmosphere by natural processes (we rely on nature because currently, we do not have technologies to remove GHGs from the atmosphere at scale economically). So it has a compounding effect in terms of temperature response over time...

Have tried to share some thoughts on this here, have a look if you like

https://ycmusings.com/1-5-its-not-a-big-deal/

I made an interactive version 4 years ago. https://callumprentice.github.io/apps/climate_temperature_ch... - I should probably update it with recent climate data.

These visualizations are so simple to understand and shocking to the core. We need more examples like this in mainstream media.

Do you think if people saw more of these in mainstream media there would be more action demanded by them from their governments/policy makers?

Yes I can see them reaching a wider audience and having more impact

Very cool and clever plot. How it was done?

I think it's based on the plots they have on big storage freezers in in the biology world. These circular plotters are used because if there's a temperature spike (power failure etc.) at midnight for some reason you can see it next day by glancing at the plot. For this, they're basically just taking the normal temperature graph plot and wrapping it around a year over and over again. Mathematically, a switch to polar coordinates would be used I think.

I find data presented in such a manner, without comment, quite a bit more compelling than much of what passes for debate these days.

All debate will soon be settled by reality.

A significant part of the debate is simply scientists going, "please, for the love of god, look at the data."

There are a few real scientists who realize there is too little actual data on a geologic scale to do anything more than paint pretty but meaningless graphs.

The majority consensus among climate scientists is that's is getting warmer due to human emissions and the error bars on "how much warmer" are not big enough to justify continuing business as usual. But even if you believe that we don't have the data for accurate predictions, that is not an excuse not to be concerned. Quite on the contrary, it could be much worse than what the IPCC reports.

>A significant part of the debate is simply scientists going, "please, for the love of god, look at the data."

Nobody! wants to look at the data. Climate change isn't about science or data anymore. It's about politics.

The first group of climate change I find are the doomers. They got bored with Mayan calendars and Y2k dates. They jumped into climate change and we are literally on the verge of extinction always. When deadlines come and go, they just give us another 10 years. Right now, we have 10 years left until we are all dead. Climate change is the equivalent of 4 nuclear bombs a second... This is also the group who sees political violence as necessary because by not solving climate change you are literally killing them. So they will be politically violent to get their way. Self-defence right?

The next group is the politicos whose 'solution' to climate change is a planned economy. Nothing really to do with fixing climate change. Unanimously voted against in the USA multiple times now. Hilariously even named after Roosevelt's new deal which never survived. Realize government expands constantly and virtually never cancels stuff. Yet the new deal by roosevelt was so destructive that it has been entirely dismantled.

The next group are the investors or financial incentives. They have significant financial benefit to see at least temporarily a big boost to climate change related stocks. Great long term investments and I have invested this way, but this group isn't about climate change, they are in it for the $.

Climate scientist? You're never going to speak against your own team. Your job security depends upon you also pushing that the climate is blowing up. Otherwise what are you being paid for?

Then you have the worst group. The 'you're a science denier' group. They have no intention to look at or even consider the data. If you don't accept the unscientific 'consensus' from financially biased climate scientists. Then you're a science denier. How about the very real problem that climate science is REALLY BAD. Nothing is ever reproduced. Nothing is ever peer reviewed. Correlation factors are less than 10%. Huge history of failed predictions and flawed systems. Climate science is worse in terms of replication crisis than psychology. Even better... this is the group who produces the illegitimate content.

https://en.wikipedia.org/wiki/Geologic_temperature_record#/m...

So what are those black/red dots for predicted 2050 and 2100 ranges? IPCC AR5 RCP8.5 is very official sounding. https://en.wikipedia.org/wiki/Representative_Concentration_P...

Seriously... the picked the most blown out of proportion prediction that is certainly not going to happen as the best option for this graph? They had to do that though didn't they.

So, the question moves to: "How to rescue the debate from the politics?"

>So, the question moves to: "How to rescue the debate from the politics?"

I'm not familiar with any issue that was rescued from politics. I very much doubt this is possible in any reasonable scenario when excluding violence.

What I was illustrating is that none of the groups in climate change care at all about climate change. If you extricate this issue from politics, it just goes away.

That’s part of the problem. There’s a large overlap between the circle of people who deny climate change and the circle of people who haven’t got the slightest clue where to get useful data or how to interpret it.

Agree visualizations are more powerful. But it would be nice to see a discussion about the data itself.

The data is accessible directly from the visualization page. But humans are very bad at looking at sheets of numbers and interpreting them quickly. Visualizations help us understand much more rapidly.

Just gotta accelerate thru this brah

Yerp, they forgot to add all the shareholder value that was created

Maybe the real treasure was the production surplus stolen from the proletariat along the way.

These are actually great ideas for discussing more figures, with a focus on the human dimensions of global change.

It's misleading to imply that this is an exponential process, rather than an S-curve. If we look where all the oil came from, we could deduce that by burning it all we would be just going back to similar environment. I.e. the absolute worst thing that could happen is a tropical paradise.

The problem is not the end state, it's the speed at which we are approaching that end state.

Think about a car moving down the highway, when you gradually apply the brake, you can safely decelerate to 0. When you hit a stationary barrier, getting to 0 is potentially deadly and also damages the car.

Rapid climate change kills species, disrupts supply chains, increases damaging weather like hurricanes, destroys agricultural lands, and erodes shorelines. All of which we could cope with over thousands or millions of years. But doing it over hundreds is going to be a catastrophe.

Agree. Still, most people seem to be under the impression that there's a "tipping point" and then temperatures will spiral into infinity.

It's disruptive, but nature and humanity is adaptive. Many species will also thrive, and total agricultural output will rise with more co2 in atmosphere.

The transition from today's world to tropical paradise would include mass extinctions and a lot of human suffering.

The real question is - is any of that human suffering going to be my own?

A "tropical paradise" at the poles, with uninhabitable equatorial regions, and untold disruption to human civilization as we know it. The transition to that global configuration is unlikely to look paradisal.

That's not likely going to happen. There are many periods in Earth history where co2 levels were way higher than now, and no large-scale desertification events are known. Periods of very high co2 and higher temperatures are known for hosting more life.[0][1] Plants and animals thrive in high co2. Less co2 has caused glacification events and loss of life.

[0] https://en.wikipedia.org/wiki/Eocene#Flora

[1] https://en.wikipedia.org/wiki/Eocene#Fauna

I didn't mention desertification, but habitability - I meant to imply "inhabitable by unprotected humans."

The Eocene saw a thermal maximum in which global mean temperature increased by about 6 ºC, and a much wetter climate: https://en.wikipedia.org/wiki/Paleocene%E2%80%93Eocene_Therm...

https://en.wikipedia.org/wiki/Wet-bulb_temperature:

> The theoretical limit to human survival for more than a few hours in the shade, even with unlimited water, is a wet-bulb temperature of 35 °C (95 °F)

https://www.nature.com/articles/s41561-021-00695-3:

> Limiting global warming to 1.5 °C will prevent most of the tropics from reaching a TW of 35 °C, the limit of human adaptation.

Fair point. How about animals? It seems that many modern mammals, including primates, evolved and thrived during the Eocene. Most of the world today is too cold for humans living without protection, so I'm not completely buying that it would be worse than today. It might require moving around a bit, but not a total catastrophe.

Cool graphic from NASA. The Earth has been around for 4 billion years. When we have 1 million year's worth of temperature measuring, we might then be able to comprehend the Earth's environment on a geologic scale as well as human impact, if any.

Is it my impression or are you denying that anthropological climate change is a thing and leaning to: only empiricism over a period that is as long as human kind has existed will enable us to know if humans are changing global climate?

Just want to know before assuming too much.

> The Earth has been around for 4 billion years.

And maybe when you've been around on this Earth for 200 million years you'll understand how pissed off most lifeforms are that we are quickly eradicating the places where they live.

Reply on news.ycombinator.com