Climate Graph Latest

Climate Catastrophe: Graphs and Commentary

Full Essay: click here for short version

Ongoing essay: updated occasionally, last updated April 19, 2024

Some recent additions or significant changes marked with (New [date])

Climate data from NOAA unless otherwise stated.

Includes significant changes to NOAA's historic temperature data released in 2023.

Temperature anomalies from 1850-1900 average replace former anomalies from 20^th Century average.

Disclaimer: I am NOT a climate scientist! and, most definitely, NOT an “expert!”

A note on the name change

It seems that the names, “Global Warming” and “Climate Change” have recently been superseded by names like “Climate Crisis,” “Climate Emergency” and “Global Heating.” I don't think any of these names really express the gravity of the situation; so as long as we are changing names, let's go with the far more descriptive “Climate Catastrophe.”

See below for discussion of Crisis and Catastrophe

Some Meteorological Spring 2024 Highlights

(March through May 2024)
(in progress)

1. March 2024 was the warmest March on record, albeit only an insignificant 0.01°C warmer than March 2016. The last ten months (June 2023 through March 2024) were each the warmest month on record with that same name by up to 0.42°C. The seven months (Sept. 2023 through March 2024) each tied or broke the 1.5°C barrier.

2. The average concentration of carbon dioxide in the atmosphere during March 2024 was 425.38 ppm, marking an increase of 0.37 ppm in the 12-month running average as measured at the Mauna Loa and Maunakea sites. This is the largest increase on record from one month to the next, going back to 1958 when record-keeping at Mauna Loa began.

3. The El Niño / La Niña (ONI) index over the January through March 3-month period was 1.5, down from the 1.8 average over the previous 3-month period. Climate models are predicting that this El Niño will continue to wane and transition to La Niña conditions during 2024. While strong, this El Niño was well below the strength of the 2014-2016 El Niño.

4. 2,000 elderly women, arguing that lack of climate action violates their human rights, win case against the Swiss government in Europe's top human rights court. Does litigation help? You bet it does!

5. As oceans continue to warm, the Great Barrier Reef and other coral reefs are suffering what is likely to be their worst-ever case of coral-bleaching.

6. Thousands of schools in the Philippines forced to close due to extreme heat.

7. While a warming climate spells disaster for humanity, certain diseases revel in it. Puerto Rico declares an emergency as dengue fever spirals out of control. Valley Fever vastly expands its reach in the US southwest. And H5N1 bird flu is spreading, not only among birds, but cattle too. H5N1 has infected humans and may mutate and spread throughout the human population.

8. United Arab Emirates and Oman suffered catastrophic flooding. Dubai received over a years worth of rain in one day, flooding this normally dry city.

9. Pakistan and Afghanistan suffered April flash flooding that killed more than 100. April is in the dry season. The monsoon rains are not scheduled to begin until June.

10. Levees collapse in Central Russia as flood waters in the Ural River rise.

11. Amidst a severe South/Central American drought, Colombians exhorted to conserve water by showering with a partner.

12. Amidst drought in the Colorado River basin, Wall Street is buying up farmland and selling the water allotment to developments hundreds of miles away at huge profits.

13. Southern Africa is in the midst of a devastating drought. Millions in Zimbabwe will go hungry this year.

14. In parts of Africa, drought resilient camels are replacing cows as the livestock of choice. Camels were introduced in the US desert southwest in the 19^th Century, but haven't survived. Perhaps it is time to import camels again.

15. A study based on satellite images finds that 45% of China's urban areas are sinking. The problem of urban subsidence, along with sea-level rise, is not limited to China and may make many of the world's urban areas unlivable.

16. The United States remains among the world's most fossil-fuel friendly nations as the Biden administration licenses what will be the largest oil-export terminal in the United States. And in spite of pledges to stop backing international fossil fuel projects, the U.S. Export-Import Bank will provide a $500 million loan for oil and gas expansion in Bahrain.

Some Meteorological Winter 2023-24 Highlights

(December 2023 through February 2024)

1. Meteorological Winter 2023-24 was the warmest meteorological winter on record, measuring 1.56°C warmer than the 1850-1900 average and 0.13°C warmer than the previous warmest meteorological winter 2015. The three months each tied or broke the 1.5°C barrier. February 2024 became the most anomalously warm month on record, 1.63°C above the 1850-1900 average.

2. The last nine months (June 2023 through Feb. 2024) were each the warmest month on record with that same name by up to 0.42°C. The six months (Sept. 2023 through February 2024) each tied or broke the 1.5°C barrier.

3. The average temperature anomaly from the 1850-1900 period for 2023 was 1.36°C, which set a record, being 0.16°C above the anomaly for previous record-holder, 2016. Some models place the anomaly for 2023 above the famous 1.5°C barrier.

4. The last ten 12-month periods ending in February (2015-2024) were the ten warmest on record. The tenth place 12-month period ending February, 2015, was 0.09°C. warmer than the 11^th place period ending in February 2010

5. The average concentration of carbon dioxide in the atmosphere during meteorological winter 2023-24 was 423.04 ppm, an increase of 3.47 ppm over meteorological winter 2022-23, as measured at the Mauna Loa and Maunakea sites. This is the largest increase on record from one meteorological winter to the next. The 12 month running average (Mar. 2023 through Feb. 2024) was 421.70 ppm, up 2.98 ppm from the Mar. 2022 through Feb. 2023 running 12-month average. Meanwhile, global CO₂ emissions continue to rise.

6. The El Niño / La Niña (ONI) index over the December 2023 through February 2024 3-month period was 1.8, down from the 2.0 average over the November through January 3-month period. The climate models are predicting that this El Niño will wane and transition to La Niña conditions during 2024. While strong, this El Niño is well below the strength of the 2014-2016 El Niño.

La Niña conditions (index of -0.5 or lower) tend to bring cooler global temperatures, while El Niño conditions (index of 0.5 or higher) tend to bring warmer temperatures.
7. As late as October, 2023, Climate models failed to predict much of the extreme heat of the latter part of 2023.

8. Not only land temperatures; but ocean temperatures too have increased significantly in 2023. 90% of all heat trapped by greenhouse gases ends up in the ocean. Ocean heat is wreaking havoc on our earthly weather patterns. The 11 months sporting the most anomalous ocean heat are April 2023 through February 2024 (the latest 11 as of this writing).

9. Fishing boats trawling the sea floor are stirring up carbon sequestered at the ocean bottoms, possibly tripling the carbon footprint of the industry.

10. A new study of sea-sponges suggests that we broke the 1.5°C above pre-industrial times barrier years ago and that the Earth had already warmed 0.5°C by the end of the 19^th Century, which is a commonly used proxy for pre-industrial times.

11. Advances in battery technology make it economically feasible to replace fossil-fuel fired electricity generating plants with renewable energy generation, combined with battery storage for times when the sun doesn't shine and the wind doesn't blow. In the first half of 2023, 68 gas power plant projects were put on hold or canceled globally,

12. The United States' first small modular nuclear reactor power plant project was cancelled amidst delays, cost overruns and technological advances in battery technology.

13. Rising sea levels and melting glaciers are threatening to uncover and spread nuclear waste buried long ago by the United States in Greenland and the Marshall Islands.

14. Greenhouse gas emissions during the first two months of Israel's War Against Gaza amount to at least 281 thousand tonnes, more than the annual output of many countries. 99% of these emissions can be attributed to Israel, with only a minuscule amount stemming from Hamas and Islamic Jihad rockets. Almost half of these emissions are attributable to US supply flights to Israel. 281 thousand tonnes is probably a gross under-estimate, as it does not include the entire war supply chain.

15. Indeed, we are only beginning to come to terms with the vast amount of climate-wrecking emissions that global militarism wreaks upon us. Pundits have been babbling for some time about how climate change impacts our security and well-being. Little has been said about how war and militarism contribute to climate change. Perhaps 5% or more of greenhouse gas emissions are attributable to militarism. In truth, militarism makes us less secure in oh so many ways.

16. A new study estimates that Climate Change has killed 4 million people so far in the 21^st Century, and that's likely a gross underestimate.

17. COP28 was yet another failure. Fossil-fuel interests and their lobbyists again got what they wanted as COP28 failed to provide any significant remedy for the ongoing climate catastrophe.

18. The world experienced 63 climate disasters in 2023, each costing a billion dollars or more. The previous record was 57 billion dollar disasters, set in 2020. The deadliest was Medicane Daniel, a hurricane-like storm in the Mediterranean, which killed over 4,300 in Libya and Greece (mostly in Libya). The most expensive was Typhoon Doksuri which caused 18.2 billion dollars in damages in China and dumped almost 30 inches of rain on Beijing, almost 50% more than Beijing's annual average.

19. The United States also set a record in 2023, experiencing 28 extreme weather disasters in 2023, each costing at least one billion dollar in loses. Leading the pack was the drought and heatwave in the South and Midwest which was responsible for $14.5 billion of the total $92.9 billion in loses and 247 of the total 492 fatalities. The previous record holder, 2020, experienced 22 such disasters.

20. The Smokehouse Creek Fire in the Texas Panhandle, driven by high winds and soaring temperatures, burned over 1 million acres killing two and forced the evacuation of the Pantex plant where nuclear bombs are manufactured. Smokehouse Creek is the largest fire in Texas history and may have been caused by a rotten utility pole that blew over in the wind. It's only February, folks. Wait until July.

21. The North American Great Lakes were virtually ice-free over much of the winter. As of March 7, ice coverage was a mere 2.2%.

22. US President Joe Biden has put permits for new export terminals for liquified natural gas on temporary hold. While hailed as a huge environmental victory, beware! Given Biden's environmental record, this could easily be reversed after the November election.

23. The $1.2 trillion Infrastructure Investment and Jobs Act, which was supposed to expand green infrastructure is being used for highway expansion and may cause an increase in greenhouse gas emissions.

24. California was pounded by two intense atmospheric rivers in early February.

25. El Niño has brought giant waves to the California coast. Wonderful for surfers; but tough on an erosion-prone coastline.

26. The Caribbean Island of Bonaire has sued The Netherlands for failure to protect it from climate change. Bonaire is a “special municipality” of the Netherlands. Special municipality appears to be a polite phrase meaning colony.

27. The Central American drought has disrupted traffic through the Panama Canal.

28. Nearly 11,000 in Ecuador were affected by heavy rains fueled by climate change and a strong El Niño.

29. While deforestation fell by 50% in Brazil's Amazon region in 2023, deforestation increased by 43% in Brazil's Cerrado grasslands to the south and east, wiping out a significant portion of the gain in the Amazon rainforest.

30. Central Chile, which has labored under a severe megadrought for over a decade, was devastated by wildfires that killed over one hundred and caused billions of dollars in damages.

31. The Congo experienced its worst flooding in 60 years, leaving hundreds of thousands homeless.

32. A new study has found that Greenland's ice sheet is retreating at a rate 20% above what was previously thought. Greenland is losing 33 million tons of ice per hour according to this study.

33. Amidst shifts in the Earth's crust, likely contributed to by the melting of glaciers in a warming climate, the town of Grindavik, Iceland is fighting a battle against lava flows from volcanic fissures that have lay dormant for 800 years and now threaten to engulf the town.

34. The UK will exit from the 1994 Energy Charter Treaty that allows fossil fuel corporations to sue governments for “lost profits” while transitioning to clean energy technology.

35. First Eurasia, then North America: were gripped by intense winter cold. 1,000 vehicles were trapped on a major highway in Sweden for 24 hours in an intense winter storm.

36. Russia, a major global supplier of fossil-fuels, complains of Europe's so-called renewable energy transition.

37. Cyclone Jasper struck northern Australia as a category 2 cyclone, causing unprecedented flooding. Jasper was the wettest tropical cyclone on record to hit Australia, dropping over 85 inches of precipitation in places.

Click here for highlights from previous months.

�But if the watchman see the sword come, and blow not the trumpet, and the people be not warned: if the sword come and take any person from among them, he is taken away in his iniquity: but his blood will I require at the watchman's hand.^*� —Ezekiel 33:6 (KJV)

^* I will hold the watchman accountable for his death.

Some Historic Temperature Graphs and Commentary

Monthly temperature anomalies: 2013-present

Table: Ten warmest 12-month periods

12-month overlapping temperature anomalies 1968-present

12-month overlapping carbon dioxide in atmosphere 1968-present

A very short term, one year, graph of CO₂ in the atmosphere

The missing graphs

3-year overlapping temperature anomalies: 1850-present

Notes on the IPCC and 1.5°C and Avoiding Extinction.

Can Science Save Us?

Discussion of Climate Crisis and Climate Catastrophe

The Future

Global Temperatures: 1700 years (Michael Mann)

Global Temperatures: 11,300 years (Holocene) (Shaun Marcott)

Global Temperatrures: 800 thousand years (Pleistocene, Holocene)

Global Temperatures: 66 million years

Global Temperatures: 542 million years

Highlights from previous months

Monthly temperature anomalies: 2013-present

How to read this graph:

1. This graph compares each month separately to the 1850 - 1900 average (for months of that same name only) and ranks them separately. In other words: The month of March is compared only to other Marches. The month of September is compared only to other Septembers.

Note: The period 1850 through 1900 is used as a proxy for pre-industrial times by the IPCC and many others. See discussion of the IPCC and 1.5°C. below.

2. For example: The warmest March, June and October are all colored red. The second warmest January, August and December are all colored orange. The March colored light blue (2014) is between the 11th and 15th warmest Marches inclusive and is 0.98° C. warmer than the average of all Marches between 1850 and 1900 inclusive. The December colored yellow (2019) is the third warmest December and is 1.27° C. warmer than the average of all Decembers between 1850 and 1900 inclusive. Etc.

3. When there is a tie, the tying months are all given the highest rank. For example, May 2016 and 2023 are both colored orange (second warmest). No May is colored yellow (third warmest).

Some points to note:

1. The data for this graph come from the National Oceanic and Atmospheric Administration (NOAA)'s climate at a glance section.

2. This graph gives the Earth's approximate average surface temperature relative to the base period, 1850-1900 for each month. Needless to say, distilling the world's climate into one number per month is a gross over-simplification. Further, surface temperature is only part of the story. Temperatures in the upper atmosphere and ocean depths contribute to surface anomalies through convection and heat exchange.

3. Temperature anomalies are not distributed equally around the globe. A map in this article from CBS news shows that the Arctic has warmed to a far greater degree than average. The North Atlantic where a weakened Gulf Stream terminates has actually cooled.

4. The nine months, June 2023 through February 2024, were each the warmest months on record with that same name (although not the nine most anomalously warm months on record). The temperature anomalies from the 1850-1900 base for Sept. 2023 through Feb. 2024 were all at or above 1.50°C.

5 Meteorological Autumn 2023 was the warmest meteorological autumn on record, measuring 1.58°C warmer than the 1850-1900 average and 0.40°C warmer than second place Autumn 2015. Meteorological Winter 2023-24 was the warmest meteorological Winter on record, measuring 1.56°C warmer than the 1850-1900 average and 0.13°C warmer than second place Winter 2015-16.

6. Antarctica experienced its lowest sea ice extent on record throughout most of 2023. Thousands of penguin chicks died because of the warming climate. The annual maximum sea ice extent reached in September was the lowest on record.

7. Ocean temperatures rose precipitously beginning in April 2023. Ocean temperatures off the coast of Florida reached hot-tub levels, 101.1°F in July. For the world's oceans, The last 11 months, April 2023 through February 2024, were the 11 most anomalously warm months on record (relative to the 20th Century average).

8. June 2021 was the seventh warmest June globally, but the warmest June in North America. It was responsible for the Pacific Northwest heat dome which killed at least 1000 people and was thought at the time to be the most extreme heat event that Planet Earth has experienced since record keeping began.

9. In early 2023 NOAA made significant modifications to its historic data. Some monthly temperature anomalies changed by as much as 0.22°C. This is to be expected. As we learn more and our historical knowledge grows, our numeric results should become increasingly accurate. NOAA continues to revise its historic temperature estimates, although changes lately have not been so drastic.

10. In spite of the wide month to month variation, this graph shows a short term rising trend from 2013 to the present. The large crests in early 2016 and late 2023 through 2024 roughly follow strong El Niño episodes and the lesser crest in early 2020 follows behind a weak El Niño. The troughs in between these crests roughly correspond to La Niña episodes.

11. 2010 (also an El Niño year) was the warmest year on record before this graph. It was surpassed by 2014, 2015, 2016 and now 2023 (in that order) as the warmest year on record. 2023 was 1.36°C warmer than the 1850-1900 average and 0.16°C warmer than second place 2016.

12. July 2023 was the warmest July on record, 0.26°C warmer than second place July 2019. Since July tends to be the warmest month of the year, July 2023 may well be the warmest month on record despite the unprecedented heat of the last six months.

13. All of the five warmest months of each name (except January 2007 which tied for fifth warmest) lie between January 2015 and the present. Beginning with January 2015, all months have an anomaly from the 1850-1900 average greater than or equal to 0.89°C. and all but three lie within the top ten warmest with that same name.

14. The last month with a negative anomaly (distance from the 1850-1900 average, a commonly used proxy for pre-industrial times by the IPCC and others) was October 1976. The last month with an anomaly less than 0.8°C was July 2014. The highest anomaly was in February, 2024, 1.63°C. We now have eight months with anomalies of 1.5°C or greater, September 2023 through February 2024 and February-March 2016.

15. Other models, such as ERA5, which is now used at the Copernicus Climate Change Service give somewhat different results. For example Copernicus shows the anomaly above the 1850-1900 base for 2023 as 1.48°C as opposed to NOAA's 1.36°C. Copernicus gives a rough comparison of several popular climate models here.

Which model is correct? All and none. Models are simply simplifications of the real world. No model of a complex system is exact (otherwise it wouldn't be a model). Complex mathematical models are full of assumptions and educated guesses. Nevertheless, short of clairvoyance, they appear to be the best we have; so yes, use them and refine them; but one would be wise not to put too much trust in them, particularly in times of rapid change.

(New Feb. 2024)
Indeed, as some have noted, climate scientists and their mathematical models have been unable to keep up with the fast pace at which our climate is deteriorating. Instead of predicting the future, they are constantly playing catch-up. As Thomas Neuburger put it, �Everything in the climate prediction world is wrong to the slow side. Things are happening sooner than anyone thought they would.�

16. The last ten 12-month periods ending in February (2015-2024) have been the ten warmest on record. The 11^th warmest 12-month period ending in February 2010 was 0.09°C cooler than the tenth warmest 12-month period ending in February 2015. (See table below.)

17. Temperatures appear to have risen about 0.35°C. over the last ten years (difference between average anomaly of 36 months ending in February 2024 and average anomaly of 36 months ending in February 2014).

Why is this graph important?

1. This is a “you can't see the forest for the trees” graph. Forests are important; but so are individual trees. Indeed, there is no forest without the trees.

2. This graph allows you to see the present in detail. (present here meaning the approximate average monthly surface temperature over the latest 11+ years.)

3. You can get a similar graph from NOAA's Climate at a Glance section; but I like the way this graph presents the data. I think the color coding increases readability and presents important data and the change of base to 1850-1900 is consistent with the use of the 1850-1900 period as a proxy for pre-industrial times.

4. Why 11+ years? Why not some other period like 7 or 15 years? No particular reason. With a longer period the lines get squished together and are harder to read. Shorter periods show less data. This started out as a ten year graph but has grown longer or shorter as I add or remove months.

5. From here on, this graph and others below will be updated only occasionally, perhaps once a quarter.

6. How did I get into this? In 2016 my favorite website for news and commentary, Common Dreams, used to report the NOAA data month after month as they set new records. They stopped when September 2016 fell to second place. Being curious, I went to the NOAA site and wondered why it wasn't reported as news that the three warmest Septembers on record were in 2015, 2016 and 2014 (in that order). After a few months of silence, I decided to start reporting these data myself. (Sept. 2016 has since been upgraded and now surpasses Sept. 2015.) Both Septembers 2015 and 2016 have been surpassed by Septembers 2020 and 2023.

A longer term temperature graph — 55+ years

1. This 55+ year graph of 12 month overlapping periods measures the temperature anomaly from the 1850-1900 average. The colors refer to the El Niño / La Niña (ONI) condition during the three month interval centered on the final month of the 12 month period.

2. The 12 month running average has risen consistently throughout 2023-24 as La Niña conditions waned and gave way to strong El Niño conditions, reaching 1.42°C in February 2024.

3. El Niño / La Niña (ENSO) refers to cyclical changes in atmospheric and oceanic circulation patterns over the tropical Pacific Ocean. El Niño episodes usually bring warmer global surface temperatures; La Niña episodes usually bring cooler surface temperatures. There is a brief explanation of El Niño and La Niña here.

An ONI (Oceanic Niño Index) is computed for each overlapping period of three consecutive months based of conditions in the tropical Pacific Ocean. If the ONI index is at least 0.5 (at most -0.5) the three-month period is considered an El Niño (La Niña) period. Five or more consecutive El Niño (La Niña) periods are considered an El Niño (La Niña) episode. An El Niño episode is very strong (strong, moderate, weak) if it contains three El Niño periods with index at least 2.0 (1.5, 1.0, 0.5). A La Niña episode is strong (moderate, weak) if it contains three La Niña periods with index at most -1.5 (-1.0, -0.5). These classifications are somewhat arbitrary.

4. The ENSO condition can cause significant changes in global surface temperatures. The table below gives estimates of annual global surface temperature anomalies relative to the 20^th Century for the six calendar years ending in 2020, assuming neutral ENSO conditions had prevailed throughout. According to these estimates, year 2020 would have been the warmest of the six years by 0.03°C.

(New Jan. 2023)
5. A more recent estimate also found that without the El Niño / La Niña effect, 2020 would have become the warmest year in the record, followed by 2022.

6. This graph is surprisingly smooth in spite of all the crests and troughs.

7. Exceptionally high temperature crests have followed the two very strong El Niño episodes of 1997-98 and 2014-16. Surface temperatures have fallen after the end of these El Niño episodes but remained much higher than before the El Niño episode began. This happened to a lesser extent after the moderate El Niño episode of 2009-2010 and the weak El Niño episode of 2018-2019. We are headed for another high temperature crest now as the current El Niño episode peaks.

8. Temperatures fell over the 2020-21 period as we experienced the start of a 3-year-long moderate La Niña episode. However the fall is not nearly as long as might have been expected. After mid-2021, temperatures leveled off and then rose somewhat in spite of the 3-year-long moderate La Niña episode which ended in early 2023. Temperatures have risen substantially since the start of the current strong El Niño episode and have surpassed all previous highs.

9. This graph consists of a progression of waves (heat waves) with increasingly high crests and troughs. Crests and troughs are marked with black dots and connected with black lines.

Crests are local maxima which are greater than or equal to all readings to the left. Troughs are local minima that are lower than or equal to all readings to the right. If more than one crest lies between two troughs only the rightmost crest is marked. If more than one trough lies between two crests only the leftmost trough is marked.

10. Crests have increased from a height of 0.39° C. (above the 1850-1900 average) in 1973 to the current 1.42°C in February 2024, with temperatures still rising. Troughs increased from a height of 0.08° C. in 1976 to 1.03° C. in 2018. On the whole, temperatures appear to be accelerating at a super-linear rate.

11. Climate-wise, extrapolation and long-term prediction are very risky endeavors. However, looking at the two graphs above, I would not be surprised to see 12-month running averages exceed 1.5°C above the 1850-1900 average within the next few months. We have already seen eight individual months reach or exceed 1.5°C. Some climate models already place the 12-month running average above 1.5°C.

12. In short: We're in terrible trouble. We better do something quick.

Another 55+ year graph — CO₂ in the atmosphere

1. The data for this graph come from the average monthly readings for CO₂ in the atmosphere, taken at the Mauna Loa / Maunakea sites in Hawaii. Each line in the graph is a weighted average of 12 consecutive months. (E.g.: The line for March 2018 is the weighted average of April 2017 through March 2018.)

Note: In February 2021, NOAA updated its monthly readings from the WMO CO₂ X2007 scale to the WMO CO₂ X2019 scale. Due to this change in scale, some monthly readings have changed by as much as 0.32 ppm (parts per million) and some 12 month averages have changed as much as 0.25 ppm. The entire graph above has been updated to the X2019 scale which is described here.

Note: Because of the recent eruption at Mauna Loa, from December 2022 through July 4, 2023, readings were taken at the nearby Maunakea observatories.

2. The average at Mauna Loa / Maunakea for the 12 months ending in February, 2024 is 421.70 ppm. The global average is thought to be somewhat less than the readings at Mauna Loa.

3. CO₂ (and other greenhouse gases like methane) in the atmosphere act like a one way glass allowing incoming electromagnetic radiation from the sun to pass through the atmosphere, but trapping outgoing radiation from the Earth, thereby warming the planet.

4. For each month since the end of 1974, the change in the 12 month running average from month to month has been positive. The monthly change since 1968 ranges from -0.03 to 0.35 ppm. The average yearly increase over the period covered by this graph (since 1968) is 1.79 ppm (parts per million). The average yearly increase over the past decade is 2.47 ppm, 38% above the average yearly increase since 1968.

5. The increase from the 12 months ending in February, 2023 to the 12 months ending in February, 2024 was 2.98 ppm, 67% above the average 12-month increase since 1968. The increase from meteorological winter 2022-23 to meteorological winter 2023-24 was 3.47 ppm. This is the largest increase on record from one meteorological winter to the next. Meanwhile, global CO₂ emissions continue to rise. We appear to be walking backwards away from the Paris Climate Accord goals.

6. In August 2023 the 12-month running average exceeded 420 ppm for the first time since record-keeping began. 420 ppm is 50% more than the 280 ppm thought to be the pre-industrial concentration. The 12 month CO₂ concentration has now surpassed 421 ppm.

7. The monthly record for the year for CO₂ in the atmosphere is typically set in May, when northern hemisphere trees come out of dormancy and begin to sequester CO₂ in earnest. CO₂ concentrations in the atmosphere typically fall from June through September and then rise again from October through May as northern hemisphere trees go into winter dormancy.

8. One usually sees these graphs of CO₂ in the atmosphere as a succession of waves rising higher each year (Keeling curve); but I like this graph of 12 month running averages, because it shows the steady month to month increases of CO₂ in the atmosphere. Also, the almost solid gray at the bottom of the graph gives the impression of CO₂ rising and filling the atmosphere. (CO₂ is actually a transparent colorless gas.) Some folks like the waves better and liken them to the rhythm of the Earth breathing.

9. In addition, this graph demonstrates through its concavity that the change in the running 12 month average of CO₂ in the atmosphere has been increasing.

10. The month of February, 2024 set a new record for CO₂ in the atmosphere, 424.55 ppm, surpassing the record set in May 2023 by 0.55 ppm. Over the period covered by this graph, the month of February never set a record until 2010. Since 2010, 6 of 15 Februaries set a record as the month with the highest concentration of CO₂ in the atmosphere. This could reflect an increase in CO₂ produced by human activity, a failure of forests, oceans or other carbon sinks to absorb CO₂, and/or other factors. In truth, we'll never attain the goals of the 2015 Paris Climate Accord this way.

(New Nov. 2023)
A very short term, 1 year, graph of CO₂ in the atmosphere

1. This graph of 30-day average concentrations of CO₂ in the atmosphere at Mauna Loa begins in November 2019 and runs through December 1, 2020.

2. During the period, December through May, concentrations of CO₂ in the atmosphere should be expected to increase, leveling off or beginning to decrease toward the end of May.

3. In December, the 2019 novel coronavirus, SARS-CoV-2, was confirmed. The ensuing pandemic caused a sharp decrease of economic activity in China, where the pandemic started.

4. 30-day average concentrations of CO₂ appear to have quickly responded, beginning to level off in mid-February, peaking at 414.43 ppm during the 30 days ending on February 25, and falling to 414.06 ppm by the 30 days ending on March 13. This cannot easily be explained by simple natural variation (see An Inquiry into a Possible Relationship between Socio-Economic Disruptions and Atmospheric CO₂ Concentrations).

5. 30-day average concentrations of CO₂ rose again to 414.80 by the 30 days ending on April 1 and peaked at 417.32 by the 30 days ending on May 28, seeming to make up for the mid-February through mid-March decrease. The most likely explanation seems to be the resurgence of economic activity in China concomitant to the Chinese bringing the COVID-19 pandemic under control in China. The blue area on the graph represents expected atmospheric CO₂ concentrations between February and April inclusive that do not appear in the record.

6. It would seem that CO₂ concentrations in the atmosphere did not respond to the pandemic in other countries the way they did in China.

7. “Experts” claim that this dip in CO₂ concentrations could not possibly be caused by the pandemic induced economic slowdown; however, to my knowledge, they have no other explanation to offer, except natural variation, which seems highly unlikely.

8. The only other recent years that have exhibited similar behavior were 2008 and 2022. 2008 was a year of another great economic disruption that started in late 2007. 2022 also saw great economic disruptions from the Russo-Ukrainian War which began on Feb. 24, 2008. 2008 and 2022 both exhibit a far more pronounced February-March dip than 2020. The chance of this unusual behavior, appearing in the only three recent years that came at the start of a great economic upheaval, being due to natural variation are minuscule. No other recent year has exhibited such an economic disruption or such a February-March dip in atmospheric CO₂.

9. If the conjecture that the dip in atmospheric CO₂ was caused by the economic disruptions holds, it is possible that we could reverse global warming by simply suspending much of our economic activity.

10. However, it should be noted that this has had little, if any, overall effect on atmospheric CO₂. Average atmospheric CO₂ concentrations rose by 2.36 ppm in February 2020 over February 2019 and by a somewhat greater amount in each subsequent month through November 2020. In addition, CO₂ emissions, which had fallen during 2020, rebounded and by 2022 had surpassed 2019 levels. By comparison, the 55 year average 12-month increase in atmospheric CO₂ is 1.79 ppm. (See previous graph.)

11. I find this graph of 30-day running averages interesting as it contains short-term information that gets lost in viewing only monthly graphs.

12. The above graph is surprisingly smooth except for the “missing piece” for the 30-day periods between late February and early April. I liken the missing piece to the bite of a huge dragon. My wife thinks it is more like the nibbles of a bevy of bunnies.

The missing graphs

Here should go historic graphs on global land use, droughts, desertification, floods, cyclones, wildfires, etc. Sadly, I have no such graphs, and not even the data to make them. Maybe later.

1. Climate v. Weather: Weather is what you see outside your window. It changes hour by hour, day by day. Climate is the sum total of weather (and other factors) over a period of years, decades, centuries or longer. Yes, it changes too; but in most cases, slowly. Anthropogenic climate change is climate change caused by human activities.

2. Weather is by nature extremely variable and extreme events have, at least until recently, been by nature rare. This makes it difficult to attribute any particular extreme weather event to climate change. And because such events are rare, it is difficult to achieve statistical significance. Another difficulty is that minor differences in weather related variables can make the difference between a devastating event (like Hurricane Harvey in 2017) and an event that causes far less destruction (like Hurricane Barry in 2019).

(New Jan. 2022)
3. Lately, extreme weather events have become more extreme and more common. The World Meteorological Organization has found that between 1970 and 2019, extreme weather disasters driven by climate change have increased five fold, killing more than two million people and costing $3.64 trillion in total losses.

4. Consider: Devastating fires in California in 2020 and 2021; exceptional heat, drought, floods and fires during both Australia's 2018-19 and 2019-20 summer; record-breaking heatwaves in the Arctic, a record breaking 2020 Atlantic hurricane season and a near record breaking season in 2021; 1/3 of Pakistan flooded in 2022, and the longest, most intense and most ubiquitous heatwave ever recorded in 2023. Climate models can help to explain these events. I've yet to see any other reasonable explanation.

(New June 2022)
5. However, attempts to attribute individual weather events to climate change have been, for the most part, disappointing. This June 2022 article from Science may give you a feeling for how little progress we've made in attributing individual events to climate change.

(New June 2022)
6. Even so, there comes a time when one must say that natural variation and coincidence are so unlikely that they must be discounted. The sheer number, destructiveness and variety of recent extreme weather-related events, as well as the lack of any reasonable explanation other than climate change, leaves little room for doubt that in the aggregate, climate change is at fault.

(New June 2022)
7. The June 2021 heat dome over western North America may have been at the time the most extreme heat event recorded on Earth. Climate models, however, were unable to predict the occurrence of such an extreme event.

(New June 2022)
8. The World Weather Attribution Initiative declared at the time that the June 2021 heat dome would have been “virtually impossible” without climate change. This statement may well have been an “overreach.”

(New September 2023)
9. Nor were climate models able to predict the extreme widespread heat which lasted throughout the summer of 2023 and affected every continent. Indeed, climate models have been unable to keep up with the fast pace at which our climate is deteriorating.

10. I think that no one has understood the relationship between climate and weather better than Joseph Conrad, who wrote in Typhoon (1902):

�Had he been informed by an indisputable authority that the end of the world was to be finally accomplished by a catastrophic disturbance of the atmosphere, he would have assimilated the information under the simple idea of dirty weather, and no other, because he had no experience of cataclysms, and belief does not necessarily imply comprehension.�

11. Conrad's Captain MacWhirr sailed his ship into the eye of a typhoon, and then brought her battered and bruised into port. Would that the captains of our Ships of State could show such dedication and tenacity.

(New Jan. 2022)
12. Joseph Conrad was a sailor during the latter part of the 19^th Century. He knew weather as few do today, and had a healthy respect for the power inherent in natural forces. Consider this quote from Heart of Darkness (1898):

�And this stillness of life did not in the least resemble a peace. It was the stillness of an implacable force brooding over an inscrutable intention. It looked at you with a vengeful aspect.�

An even longer term temperature graph — 174 years

1. This graph (also from NOAA data) of 36 month overlapping averages (each 36 month period ending in the month with the same name as the latest month for which data is available) from 1850 to the present shows a longer term rising trend, with an increasing rate of warming in recent years.

2. I like 36 month overlapping graphs. I think they smooth the data, but not too much. You can view 12 month or 60 month overlapping graphs at NOAA's Climate at a Glance section too.

3. There have been various pronouncements that global warming stopped in 1998 (or some other recent year) and global cooling began. This graph demonstrates clearly, without the need for any statistical analysis, that no such thing has happened.

4. Data previous to the 1960s are from surface-based measurements and probably not as accurate as data from later years which include satellite-based measurements.

5. This graph begins with 1850, about a century after the start of the industrial revolution. It details the sharp and increasing rise in global temperatures with the development of technology from around 1910 to the present. It should be noted that the period 1850-1900 is not pre-industrial, although it is used as a proxy for pre-industrial times by the IPCC and others.

6. This graph also details an even sharper, unprecedented rise in global temperatures beginning around mid-2014 and continuing through mid-2016; followed by a leveling off of global temperatures after mid-2016. The rise from mid-2014 through mid-2016 roughly coincides with a monster El Niño episode.

7. 36-month average temperatures appear to have begun to rise again in 2024.

Some notes on the IPCC, 1.5° C. and Avoiding Extinction

The Intergovernmental Panel on Climate Change (IPCC)

1. Thousands of scientists contribute to the assessments of the Intergovernmental Panel on Climate Change (IPCC). Good science is not done by committee — never has and likely never will be. If Albert Einstein had to work with a committee like the IPCC, we might still be struggling without a theory of general relativity.

2. The “IPCC Special Report on Global Warming of 1.5�C” (2018) notes that there are few direct temperature measurements from before the industrial revolution, so they declare that they will use 1850-1900, the earliest period from which there exist near-global observations, to represent the “pre-industrial” period which ended a century earlier.

3. I don't get it. Why don't they just drop the “pre-industrial” and say they are measuring warming from the latter half of the 19th Century? And just how do they know that 1850-1900 is a good representation of pre-industrial temperatures when there are so few direct measurements? And which part of the pre-industrial period are they talking about? This is important. The historical record shows periods, such as during the 14^th and 15^th Century, in which the climate changed abruptly. (See Global temperatures: 1,700 year graph below.)

4. I think “pre-industrial” should mean before the start of the industrial revolution which is generally considered to have begun sometime between 1750 and 1800. In this case, pre-industrial should mean the period immediately before the start of the industrial revolution. I find this conflating of the second half of the 19^th Century with pre-industrial times confusing at best and perhaps even a deliberate obfuscation. (Sorry folks. Consider this as coming from an unrepentant paranoid conspiracy theorist.)

(New Feb. 2024)
5. Indeed, a study of 300-year-old sponges by Malcolm McCulloch suggests that the Earth had warmed by 0.5°C by the latter half of the 19^th Century. This would throw all pronouncements about global warming since pre-industrial times off by −0.5°C.

(New Jan. 2024)
6. I note that climate scientists and other commentators now tend to use phrases like “reference period” or “surrogate” to describe the relationship between the pre-industrial period and the period: 1850-1900. This lends some clarity to the situation.

7. Whereas the temperature differences between pre-industrial times and 1850-1900 are still thought to be negligible (in spite of Sponge Bob) and we estimate the 20^th Century average at 0.17° C. above the 1850-1900 period, the latest ten years (2014-2023) measure an average 0.94° C. above the 20^th Century average for a total of 1.11°C (accounting for round-off error). Who says global warming is a hoax?

8. Note: NOAA has recently posted global temperature estimates going back to 1850. This makes the above computation considerably easier.

Why 1.5° C.?

1. Based on the recommendations of the IPCC, the Paris Climate Agreement seeks to limit global warming to 1.5�C. above pre-industrial (later redefined as 1850-1900) levels. So what's the big deal about 1.5° C. anyway?

2. If (unlike yours truly) you are a normal human being, your body temperature is probably around 37° C. (98.6° F.) Now raise your body temperature 1.5° C. At 38.5° C. (101.3° F.) you are probably feeling sick and better go to bed and drink plenty of fluids. Now raise your temperature another 0.5° C. At 39° C. (102.2° F.) you are feeling terribly weak, dizzy and disoriented. Suppose your temperature goes up yet another 2° C. At 41° C. (105.8° F.) you will die, if your body temperature does not come down very quickly.

3. The analogy is not exact. Gaia (The Living Earth) is much more resilient than we puny humans. She has weathered wilder swings in temperature than this. The climate at 4° C. above pre-industrial levels would be very inhospitable to human “civilization,” with monster hurricanes, floods, droughts, and other extreme weather events which would dwarf anything on Earth today. A 4° C. rise in temperature would cause crop failures, famine, disease, and likely, wars over Earth's dwindling resources. It's very unlikely that many of us would survive a 4° C. rise in the Earth's temperature.

Avoiding Extinction

1. In truth, I think it misguided to focus on 1.5°, 2.0° or any other number. I think it misguided to focus on the late 19^th Century, pre-industrial times, or any other period. It is distracting. We already know what needs to be done; and we know that it needs to be done now. It is quite clear and simple. We must all work together now to stop warming the Earth. We must focus on drastically reducing our carbon footprint immediately. That means giving up our addictions to fighting wars, burning fossil fuels, eating meat, building with concrete, wearing fashion clothing, having lots of babies, traveling by air, etc. etc. etc. It means planting trees, nurturing forests, walking and riding bicycles, eating locally raised foods, etc. etc. etc. Are we ready to do all that? Nothing less will do. It's hard to give up so many addictions all at once; but it may just save us from extinction.

(New Nov. 2022)
2. I have never understood why militarism is so rarely mentioned as a driver of climate change. It appears obvious. Perhaps some feel that giving up war is too big a price to pay for survival of our species.

(New Feb. 2024)
3. I note that commentators are beginning to deal with the huge contributions war and militarism make to global warming. See for example: Emissions from Israel�s war in Gaza have �immense� effect on climate catastrophe, in which it is estimated that the first two months of Israel's War Against Gaza are responsible for more CO₂ emissions than many countries contribute in a year. It is also estimated that global militarism is responsible for at least 5.5% of all human CO₂ emissions, and this study was done before Israel's 2024 War Against Gaza.

(New Jan. 2022)
4. Furthermore, we must all work together, as equals, all eight billion of us. Can North Americans, Europeans and East Asians work with Africans, Latin Americans, Palestinians, Haitians and Afghans as equals? Can they recognize that they have created the Climate Catastrophe, while up to now, others have borne the brunt of its deprivations? The addiction to privilege may be the hardest addiction of all to give up; yet it may prove to be most important. Unless we can give up our addiction to privilege, success would seem to be extremely unlikely.

(New Feb. 2022)
5. A study by Center for Global Development estimates that the average Estadounidense is responsible for emitting more CO₂ in a day than an average Congolese emits in a year. Another study by Aimee Ambrose of Sheffield Hallam University shows that the world's richest 10% are responsible for almost 50% of global CO₂ emissions; and that the gap between rich and poor is increasing. In other words, if the rich lived like the poor, our climate problems would likely be solved. However, as Ambrose points out:
�addressing excessive personal consumption is something that isn�t on the agenda for the government and policymakers.�
(New Jan. 2022)
6. There is a lesson for us in the demise of the Greenland Norse colony that died out in the 15^th Century as their North Atlantic environment turned colder. One of the major impediments to survival was a privileged caste that refused to adapt to their changing environment. Jared Diamond writes in Collapse: How Societies Choose to Fail or Succeed:

�Norse society's structure created a conflict between the short-term interests of those in power and the long-term interests of the society as a whole. ... Ultimately, though, the chiefs found themselves without followers. The last right they obtained for themselves was the privilege of being the last to starve.�

Our 21^st Century global society seems to be headed down this same path. Perhaps, we can learn from the past and turn this around.

An Exercise: Especially for Climate Change Skeptics

1. Estimate from the graphs and commentary above the probability that if we continue with business as usual, the result will be the collapse of our “global civilization.” 1%? 5%? 10%? 20%? 50%? 90%? 99%?

2. Think about at what percentage value you would recommend that the world take action to reduce global warming. 1%? 5%? 10%? 20%? 50%? 90%? 99%?

3. Think about your answers to the two questions above.

Can Science save us?

1. Well, uh, Science got us into this mess. Scientists taught us how (in the words of Joseph Conrad) �To tear treasure out of the bowels of the land ..., with no more moral purpose at the back of it than there is in burglars breaking into a safe.� But they taught us much more than that. They taught us how to make lots of money by burning the treasure and fouling the air. They also taught us how to make bombs which would render the Earth uninhabitable by humans for centuries to come, and oh so much more.

2. So can Science save us? When someone tells you they can clean up the mess they made, but you have to pay them to do it, beware. Now we're told that scientists can geo-engineer the planet to keep it cool. Lots of money to be made on geo-engineering, which, judging by all past experiences, will create even bigger problems, that scientists will be very happy to solve for an ever-increasing price.

(New Mar. 2022)
3. And scientists tell us they can show us how to keep on burning fossil fuels without adding CO₂ to the atmosphere. The US Department of Energy has wasted over $1 billion on “scientific” schemes for carbon capture and sequestration from burning coal with no positive results.

4. In general, scientists seem unable to grasp the magnitude of what they have wrought. They appear stuck in outdated thought patterns. Can we turn this around? Theoretically, I think, Yes. In practice, Unlikely.

5. I am forever indebted to Robert C. Koehler for introducing me to this Arhuaco saying:
�When you go to dig your fields, or make a pot from clay, you are disturbing the balance of things. When you walk, you are moving the air, breathing it in and out. Therefore you must make payments.�
We have been disturbing the balance for a long time, without even a thought about paying for what we take. Payment is long overdue. Nature is foreclosing.

(New Jan. 2023)
6. Perhaps it is time to start treating Nature as the powerful entity she is. We think of ourselves as being in control; but I think we have it backwards. Should Nature choose to snuff out humanity, it could do so easily, without even consulting us. Perhaps we should be showing reverence for Nature. Perhaps we should be placating Nature. Perhaps it is time we understood that we are a part of Nature, an expendable part. Nature will survive without us. We cannot survive without Nature.

Discussion of Climate Crisis and Climate Catastrophe

1. Global Warming and Climate Change are objective criteria. We can measure temperature today and compare it with measurements taken 50 years ago. Likewise with rainfall, wind velocity, cloud cover, chemical makeup of the atmosphere and other factors, all of which influence climate. The terms Global Warming and Climate Change have served us well. I suggest we stick with them. There is a consensus, not only among scientists, but among all people, particularly young people, that the world is warming and the climate changing.

2. Crisis is a different matter. Crisis is subjective. Crisis implies a turning point. How do you measure degrees of Crisis? Likewise with Catastrophe. A Catastrophe is a terrible event. How do you measure degrees of terribleness? If one doesn't take advantage of a Crisis to turn in the proper direction, one can easily create a Catastrophe.

3. Indeed, that is exactly what has happened with our climate. I've been hearing for some 20 years that the Earth is warming and we must take action immediately. I'm still hearing it 20 years later. I think we are well past the Crisis stage and into Catastrophe. So what is to be done?

Facing Catastrophe

1. Let's revisit Joseph Conrad's Captain MacWhirr. Sitting in the chart room with his ship in the eye of the typhoon, he finally realizes the folly of what he has done. He understands that the worst is to come and his ship is likely to go down with all hands on board. He says to himself, half aloud, “I shouldn't like to lose her.” And indeed, he does not. Against all odds, he sails his ship safely to port, battered and bruised.

2. Like Captain MacWhirr, I, too, “shouldn't like to lose her.” And Captain MacWhirr has sound advice for us:
“Don't you be put out by anything. ... Keep her facing it ... Facing it — always facing it — that's the way to get through. ... Face it. ... Keep a cool head.”
3. It is difficult to tell people that we are in the proverbial eye of the typhoon and the worst is to come; yet, tell them we must. How are we to face the looming Catastrophe, if we ignore its true nature?

4. Panic would not be helpful. We must face the looming catastrophe with a cool head.

“Facing it — always facing it — that's the way to get through.”
The Future

1. Many have wondered what will happen to mankind as the climate continues to warm. Some say we will continue with business as usual; others say we will join the dodos and the dinosaurs. I suspect somewhere in between. Our current “civilization” is certainly unsustainable; but I see no reason why, with the grace of God, a few of us can't continue to live on Earth in much the same way as our ancestors did during the Pleistocene, which ended about 11,300 years ago.

(New late 2021)
2. Personally, I don't think this would be a bad outcome. If we are to survive at all, we must learn our place in the greater scheme of things.

3. As the effects of climate change become more extreme, it becomes harder and harder to deny them. Unfortunately, humanity does not appear to be taking the steps necessary to ensure survival into the future.

(New Nov. 2022)
4. Bill McGuire's book, “Hothouse Earth, an Inhabitant's Guide” (2022) may help to create a sea change in public opinion. For the first time, to my knowledge, a well-respected Earth scientist has publicly stated that climate collapse is upon us and we must learn to adapt to it rather than attempt to prevent it. McGuire castigates his colleagues as “climate appeasers,” who refuse to state publicly how bad things really are, and thereby only succeed in making a bad situation worse.

�Yet will I leave a remnant, that ye may have some that shall escape the sword among the nations, ... and they shall lothe themselves for the evils which they have committed in all their abominations.� —Ezekiel 6:8-9 (KJV)

___________________

Unlike the graphs above, the graphs below are based on “proxy data.” That is: global temperatures are inferred from things like tree rings, ice cores, the makeup of the shells of sea critters, type of flora and fauna in the fossil record, etc.

Needless to say the graphs below may not be all that accurate; and the further back in time we go, the less accurate they are likely to be. Nevertheless they seem to be the best we have; so let's go with them.

1,700 year Hockey Stick Graph, Michael Mann et al.).

1. This graph is derived from research by Michael Mann et al., published in 2008.

2. The baseline, 1961 to 1990 average, is approximately 0.31° C. higher than the 1850-1900 average used in the first three temperature graphs above. The scale is Fahrenheit instead of Celsius (1.8° F. = 1.0° C.). The dark gray band represents probable uncertainty.

Temperature for the past 11,300 years, Marcott et al.

1. This graph is from research by Shaun Marcott et al. published in 2013 and represents a probable reconstruction of temperatures over the last 11,300 years (Holocene).

2. During the Holocene, mankind learned to domesticate animals, build cities, develop written languages, cut down forests, burn fossil fuels, fight wars etc.

3. The baseline, 1961 to 1990 average, is the same as the previous graph and is approximately 0.31° C. higher than the 1850-1900 average used in the first three temperature graphs above.

4. The gray squiggly lines at the right represent the previous graph superimposed on Marcott's findings.

5. The wide band represents probable uncertainty.

6. This graph shows global temperatures rising 0.5 to 1.0° C. until approximately 7000 years ago and then falling back to a low close to the start of the Holocene. This low is generally called the “Little Ice Age” which lasted, roughly, from around 1500 to around 1900. From the Little Ice Age onward temperatures have risen sharply.

7. One problem with this graph is that the right end of the x-axis (labeled 0) is “the present.” Which year is the present? This is important with temperatures rising by perhaps 0.35° C. in the last decade.

8. It appears from this graph and the temperature graphs presented above that we surpassed the previous Holocene maximum temperature in 2015 and remain above it.

800,000 year temperature graph from NOAA article on global warming and climate change.

1. This graph represents a possible reconstruction of temperatures during the ice ages and the interglacial periods. (Pleistocene)

2. The scale is Fahrenheit instead of Celsius (1.8° F. = 1.0° C.) and the baseline is the average over the past millennium.

3. The Pleistocene was a succession of wide swings in temperature between ice ages and interglacials, according to this graph by as much as 16° C.

4. I have found it difficult to reconcile this graph with the previous graphs. Since the data come from ice cores, likely they do not reflect global temperatures as a whole.

5. Modern man evolved during this period, probable around 250,000 years ago. Around 50,000 years ago he began to develop more advanced technology and migrated throughout Eurasia, Africa and then Australia and even later, the Americas.

6. Since modern man has been able to survive in almost every ecosystem on the planet, it appears very likely that he will be able to survive in at least some future ecosystem.

7. The same can not be said about “civilization.” “Civilization” developed under some very specific climatic conditions that are unlikely to exist on Earth in the near future.

8. I suspect, if we have not already done so, we will surpass the highest interglacial temperatures soon. (Keep in mind that the temperature has probably risen about 0.35° C. (0.63° F.) over the past decade. (See graphs above.)

global temperatures, 66 million years.

1. I don't know where this graph comes from originally. It is all over the internet.

2. 66 million years ago marks the probable demise of the dinosaurs.

3. Temperatures in the Eocene, some 50 million years ago were likely considerably higher than they are today.

4. There are no known “great extinctions” during the Eocene. Indeed, life seems to have thrived during the warm period in the early Eocene.

5. Atmospheric carbon dioxide is thought to have also been much higher during the Eocene than today.

6. The Eocene might give us some clues as to what might happen on Earth in the near future.

global temperatures, 542 million years.

1. I don't know where this graph comes from either. It is also all over the internet.

2. The combination of linear and logarithmic scales on the x-axis is somewhat confusing, but allows for extra detail to be shown in more recent times.

3. 542 million years, back to the Cambrian, is a long time. Planet Earth has weathered a lot of changes. May she also weather this one.

4. Looking at these graphs, one should realize how hard it is to predict the future. Science talks in probabilities. There are few certainties in Science.

More discussion of these and other temperature graphs to be added later

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