Climate Change, Immigration And Population Decline
It’s All More Or Less Connected, Somehow
In 1972, a group of scientists — the Club of Rome — published a book called “Limits to Growth”. It contained the results of a simulation of the world’s population, environment, and economics. It predicted societal and environmental disaster if the world didn’t become a “no-growth society”. It must have been 7 or 8 years later when my brain was developed enough to tentatively defend the book’s recommendations, thereby sending an Austrian banker through the roof of my uncle’s dining room.
The model’s dire predictions of looming environmental disaster startled people. The backlash was severe. Hostile critics picked at every detail of the model’s assumptions[i], trying to invalidate its message. The issue has been hotly debated ever since.
Despite its controversial nature, or perhaps because of it, the Limits to Growth model made one point emphatically obvious: simulation models are capable of making important contributions about complex problems of global importance.[ii]
Now we know that many of the book’s predictions turned out to be wrong (or maybe just premature). Since then, the world has improved on many fronts, quite spectacularly on some of them:
- Extreme poverty, defined by the World Bank as living on less than $2.15 a day at 2017 purchasing power parity, has declined from 40% of the world’s population to 8%.
- Child mortality rates (deaths before age 5) in the US have fallen from 21.5 per 1,000 live births to 6.2, in Europe from 26.7 to 3.2, and globally from 96 to 26.
- The global literacy rate (the percentage of the population over 15 years old that can read and write) has increased from 67% to 87%, with 50% of all countries in the World Bank’s database now exceeding 95%.
- Rather than facing depleted food supplies and raw material reserves (oil, gold and other minerals), we keep finding and developing new ones — which is a problem with regard to global warming.
“Limits to growth” was pessimistic about it but did not predict the precise amount of CO2 in the atmosphere. Since its publication we have managed to increase the amount from 327ppm (parts per million) to 424ppm (CO2 accumulates, so it’s bound to go up over time, but it shouldn’t go up that much).
The scientists from the Club of Rome ran a simulation (called World3) which was based on the work of Forrester (MIT professor and founder of system dynamics). The model was based on key interactions between global variables for population, fertility, mortality, industrial output per capita, food per capita, services per capita, non-renewable resources and pollution.
The simulation created four different scenarios, BAU (business as usual) and BAU2 (doubling the amount of resources available) as the more likely ones and CT (comprehensive technology) and SW (stabilized world) as the unlikelier ones. Society collapses in the first two scenarios and adapts reasonably well in the latter two.
Computers are much more powerful now than in 1972 and our modeling has become infinitely better. Same as then, all our predictions rely on computer modeling, intelligent assumptions, and large amounts of data. As everybody has come to accept, our weather predictions have become incredibly precise two weeks out, not so much 10 years out. A prediction of global temperatures for 2100 comes with uncertainties, but a simulation is all we have if we want to be prepared.
The conflict lines that we see in society and therefore politics follow people’s understanding of data, beliefs in scientific logic and their willingness to accept the need for change. The public discussion has become confrontational, political and about beliefs that are often devoid of scientific logic. At the core of our divisive conflicts are often three inter-related topics: climate change, immigration and population decline. Beliefs come in packages these days, so our beliefs about climate change will dictate our attitude to immigration and vice versa. Consequently, the world’s political parties offer the same packages in every country — with local garden varieties, such as polarized attitudes towards gay and transgender rights, racial equity, abortion rights, the role of religion, the appropriate role for the government, global trade, and gun rights etc. etc.).
Almost Nobody Denies Global Warming Anymore
Times have changed. When I was in school (late 70s to mid 80s) another ice age was a much-discussed scenario, and I didn’t like the prospect of having to wear mittens in summer.
Anybody with access to the Internet or a TV must acknowledge the existence of a global warming trend. We have access to reliable data about the global average warming trend[iii]:
Since this is a global average across all geographies (land and ocean), an undifferentiated view of the numbers can be misleading. It doesn’t answer critical questions like:
- Is a 1.2C deviation from the 20th century average meaningful?
- Is it too warm now? How bad is it and is it going get worse?
- How much is 1 degree Celsius in Fahrenheit? C = (F -32) x (5/9), so 1C difference equates to 1.8F. It would be so much easier, if the US moved to Celsius, like every civilized nation.
- What are the different warming trends across the globe?
For the United States, we have the data. We used to hover around the same average of 73.6F for over 90 years and then it started getting markedly hotter in the last 30 years. This trend shows for all months of the year and every region of the United States:
So where are the global hotspots? Where is life getting hotter (we know that Greece, Italy and Spain were extremely hot but nevertheless popular tourist destinations in 2023). This is a comparison of the average deviation (anomaly) from the 20th century average, for July and January 1993 to 2023:
Europe is definitely a hotspot in July as in January, and so is North America in the winter. The biggest anomaly is in the Arctic in January, and we have all heard about the sorry fate of polar bears there. While 1 degree of anomaly sounds bearable (no pun intended), we have witnessed higher anomalies in the last 3–5 years — i.e., a +3.5C anomaly in January 2023 in Europe and North America, a +1.5C anomaly in the North Atlantic sea surface in July 2023). The anomalous trend is undeniably pointing upwards.
People argue about how meaningful the data is
It seems arbitrary that our base year to measure global warming is the average of the 20th century, but the last century is generally deemed to have provided ideal conditions for human civilization (aside from WWI and WWII, that is apparently the 20th century).
I frequently meet people who tell me that global temperatures were warmer in the old days (i.e., the Egyptians, Greeks and Romans were scantily clad and seemed to have a good time in Southern Europe and Northern Africa), and people thrived.
Our historical data (mostly obtained from lake and ocean sediments, ice cores, stalagmites) doesn’t point in that direction for global averages, although there were big differences in local climates. The ice age, which began about 2M years ago and ended about 11,500 years ago, affected both hemispheres. The brief relapse into ice age about 15,000 years ago was a phenomenon of the Northern Hemisphere while the Southern Hemisphere continued to warm.
Its end triggered a rise of global sea levels, and our legends of floods (Noah’s ark, songs and stories from Australian aboriginal traditions) derive from that period. In total, its end was conducive to human civilization but probably traumatic to local cultures in the South (i.e., there are traces of big lakes in the Sahara from around 7,000 B.C.; the Australian Aborigines have 10–15,000 year old songs about their forced relocation hundreds of miles inland to escape the rising waters).
Modern day records from pre-industrial times — the time from Jesus to 1850 — demonstrate that the “dark ages” deserved their name. Life on earth was cooler on average than today. Poor harvests, hunger, violent migration (the Mongols are coming!) and never-ending wars were commonplace. Most periods were a miserable time to be alive, especially the first 500 years — proof of what a difference 1 degree Celsius can make (or 1.8 degrees Fahrenheit).
Ironically, one degree of warming, or even two, seem like a blessing on most days of the year. Even in the summer, who would notice the difference between 25C and 26C? But we are talking about the weather and not the climate. NASA explains the difference as:
The difference between weather and climate is a measure of time. Weather is what conditions of the atmosphere are over a short period of time, and climate is how the atmosphere “behaves” over relatively long periods of time.
When we talk about climate change, we talk about changes in long-term averages of daily weather. Today, children always hear stories from their parents and grandparents about how snow was always piled up to their waists as they trudged off to school. Children today in most areas of the country haven’t experienced those kinds of dreadful snow-packed winters, except for the Northeastern U.S. in January 2005. The change in recent winter snows indicate that the climate has changed since their parents were young.
If summers seem hotter lately, then the recent climate may have changed. In various parts of the world, some people have even noticed that springtime comes earlier now than it did 30 years ago. An earlier springtime is indicative of a possible change in the climate.
In addition to long-term climate change, there are shorter term climate variations. This so-called climate variability can be represented by periodic or intermittent changes related to El Niño, La Niña, volcanic eruptions, or other changes in the Earth system.
More frequent weather extremes are one of the more tangible and undesirable consequences of global warming. A multitude of factors seems to be at play, and it is hard to discern cause and effect in this. Cloud coverage, shrinking glaciers and polar ice, La Niña, El Niño, jet streams and global warming play havoc with the weather and feed into each other. 2023 brought us unprecedented snow- and rainfalls in California in the winter, hailstorms and floods in Northern Italy in the summer, scorching heat in Spain, floods in Vermont and Canada, wildfires in many places (incl. 110 dead people in Maui) leading to orange smoke in Chicago and NYC, as well as drought and torrential rainfalls taking turns in other places. It’s all hard to deny and label as normal.
The oceans are assumed to be the most vulnerable place on Earth when it comes to climate change and global warming. Aside from apocalyptic predictions that may or not materialize in the next 100s or 1000s of years (The Day After Tomorrow), there is already an observable impact of global warming[vi] on the world’s oceans:
- Sea-level rise is accelerating, at an average rate of 4.5 millimeter per year over the period 2013 to 2021 and even higher rates in the Southern Hemisphere
- Marine heatwaves are increasing, leading to widespread coral bleaching and reef degradation.
- Loss of marine biodiversity comes with rising temperatures and is irreversible. Florida has lost over 25% of its manatee (very cute animals) population in the last 3 years, due to starvation and tide bloom. And sharks (not so cute) are searching for food in popular vacation places (Cape Cod, New York, Maine and others).
When a friend of mine served in the US Navy, he was told to dispose the ship’s waste into the ocean. Noticing his reluctance, an officer told him: “Small problem, big ocean.” In reality, our ocean’s capacity to absorb our collective crap is not as big as we think:
Immigration is at the top of societal and political conflict in every country now — and it is sometimes connected to climate change.
There is no universally correct answer to the immigration problem, but there are two wrong ones: letting nobody in or letting everybody in.
Letting nobody in not only violates principles of commonly accepted principles of humanity but is also impractical and economically damaging. Very few countries bar almost everybody from entering, North Korea being the most prominent one (North Sentinel Island, which is administered by India, is also a no-go area for outsiders).
Letting everybody in (“on this Earth, nobody is a foreigner”) may satisfy humanitarian ideals but would also quickly turn into an unmitigated disaster for the immigrants. Wealthy countries have the capacity to absorb large numbers of immigrants (legal or illegal) on an irregular basis (i.e., 6M Ukrainians registered in Europe as of July 2023, and about 1M Syrians across Europe), but not on a more frequent basis. Most populations deal better with immigrants who share their democratic, cultural, ethical, religious, or other values. Too much uncontrolled immigration of any kind tends to generate extremist political leanings, which are typically counterproductive for immigration and the integration of foreigners.
People’s motives to move to other countries (emigration/immigration or within their own countries or regions (migration) are various:
- Political or social factors
- Economic or demographic factors
- Environmental or climate factors
Within all these categories, there is legal and illegal immigration. Legal immigrants in the US can be refugees[vii] who were granted asylum or just people like me who filled out the necessary paperwork. Most immigrants get naturalized on request, after the appropriate time has elapsed (967,500 in 2022).
According to the American Immigration Council, the body of law governing U.S. immigration policy is called the Immigration and Nationality Act (INA). The INA allows the United States to grant up to 675,000 permanent immigrant visas each year across various visa categories. On top of those 675,000 visas, the INA sets no limit on the annual admission of U.S. citizens’ spouses, parents, and children under the age of 21. In addition, each year the president is required to consult with Congress and set an annual number of refugees to be admitted to the United States through the U.S. Refugee Admissions Program.
The number of legal immigration per year in proportion to the US population can be seen here[viii] (I had to use a base-3 logarithmic display, because the immigration numbers are so small that they would be invisible in comparison to the US’s total population):
We had about 750,000 admissions in 2021, which equates to 0.22% of the total US population. The highest absolute number is from 1990, when the US admitted 1.5M or 0.62% of the total population. In percentage terms, the highest number was admitted in 1850, 1.6% of the total population of 23M. About 46M of today’s residents of the US were born in another country (Center for Immigration Studies).
There is also illegal immigration, which has several difficult-to-measure components:
- We estimate that there are about 11M — more or less tolerated — illegal immigrants who live in the US (Pew Research Center)
- In 2022, the US border patrol turned away about 2.8M potential immigrants
- Maybe 1M illegal immigrants found their way into the US
- Many more potentially illegal immigrants are waiting in Mexico, under a US-Mexican agreement[ix]
The European Union[x] (a collection of very different countries — from tiny Liechtenstein which doesn’t allow almost any immigration to Spain, France and Germany, which are supposedly the friendliest to immigrants) with a population that’s 34% higher than the US’s, on 4M km2 (or 1.7M sqm, which is 55% smaller than the US) has to deal with far higher regular numbers than the US and lower illegal numbers and gets overwhelmed by refugees from the world’s crisis areas from time to time:
- 3.9–4.8M illegal immigrants live in the European Union (EU), (Pew Research Center)
- By some estimates, 200–300k illegal immigration attempts to the EU occur per year (Frontex), with numbers and fatalities rising — mostly on the dangerous crossing of the Mediterranean Sea
- 2.5–3.5M first residence permits get issued to non-EU citizens per year, depending on the level of refugees in any given year
- 38M inhabitants were born outside the EU
- What Mexico does for the US in containment of illegal immigration, Turkey does for the European Union, and it’s not pleasant for the (millions of) people affected by it
Long term predictions of environmentally driven (im)migration are gloomy
Current numbers seem to be rather small or immeasurable. There are estimates that environmental factors will bring up to 1M immigrants to Europe by the year 2050 (The Guardian 2017) and we will face a global total of 1.2B displaced people in 2100 (IPE Thinktank, www.zurich.com), but there is no way of knowing.
The World Bank’s Groundswell model predicts significant internal migration movements until 2050 — between 44m and 216m people in Africa, Asia, Eastern Europe, Latin America and the Pacific islands could be on the move within their own countries.
In today’s world, we cannot attribute significant numbers to environmental factors, unless we see the world’s current wars as an outcome of global warming (this may be true for Syria, which is a hot and dusty place). For now, poverty and bad governance are much bigger factors in immigration than climate change.
Fear of population decline is on the rise
When people refer to population decline, they often mean decline before immigration. In total, most countries and the world as a whole have seen population growth in the last decades. Almost all developed nations fail to achieve the minimum birth rate of 2 children per woman (because on average, one woman and one man need 2 children to maintain a stable population). The current actual number for the US is 1.66, for the European Union it is 1.53, for China it is 1.28 etc. etc. — Africa beats everyone with 4.24 children per woman, but their numbers have peaked too. Despite this, the US grew from 224M in 1980 to 334M in 2023 (a little under 1% per year), and a small country like Austria grew from 7.5M to 9M (0.4% per year), all thanks to abundant and sometimes unpopular immigration.
In many developed countries there is a notion — regardless of political leanings — that an anxiety about the future (with climate change being a major factor and the “last generation” gluing itself to streets and artwork in Europe) keeps people from having children. It is probably not income inequality that keeps people from having children, as there is a clear negative correlation between income and birth rates, with the poorest part of the US society having the highest number of children[xi] (although, in some wealthy circles here, it is a status symbol to raise 5 or 6 children).
The only remedy seems to be in tolerating or even encouraging increased immigration. And this is where our political and societal conflict comes to a boil, very much depending on political leanings. On the extreme side, people fear a radical change to our societies’ ethnic mix, with the US becoming more Hispanic and Europe becoming more Arab or African, as those ethnic groups have more children than our “native” population — at least that’s what some people think.
Luckily, we have good statistics in the US! We know the fertility rate per ethnicity[xii] (the French government prohibits that kind of data collection):
Based on this, we can extrapolate to our most likely population mix by year 2050, and it will change like this (not by much):
Birth rates alone won’t change the composition by much, but immigration definitely will. In a simple mathematical model with zero natural population growth and about 1M mostly Hispanic immigrants per year, their share will have increased to roughly 35–40% of the US population by 2050.
Whether people like that or not is very much a question of preferences. Certain groups articulate a preference for Caucasian immigrants (or even Norwegians[xiii]), although I never understood what makes Southern Russians particularly attractive as immigrants. Everybody should be reminded about the arduous journey of other immigrants — many their ancestors — to social acceptance, from the Irish (a drunken, riotous lot after whom the paddywagon — a police car for prisoners — was named) to the Italians (considered racial pariahs in the 19th century and gradually accepted as “white” people in the 20th century[xiv]) to Jewish people.
People follow their beliefs when it comes to fighting climate change
As an extreme attitude, climate denialism has been replaced by climate doomism[xv]:
“We’re doomed,” said a typical social media post last month, as authorities confirmed Earth had had its hottest June on record. Rapid warming “will wreak destruction for life on Earth” long before 2050, warned another after July became the hottest month on record.
These are not the first signs of climate doomism. US writer Roy Scranton published a book in 2015 called Learning to Die in the Anthropocene, about finding meaning amid “the collapse of global civilisation”. Jem Bendell, a British professor, produced a paper in 2018 that spawned a “deep adaptation” movement based on the belief that most of the world would soon face climate-influenced societal collapse.
Researchers studying 10,000 young people in 10 countries two years ago found 56 per cent of them agreed “humanity is doomed” and 76 per cent thought the future was “frightening”. And that was 2021, long before 2023 saw ocean waters off Florida warming to hot tub levels and a striking lack of midwinter Antarctic sea ice.
I do not blame anyone who fears for the future today. The number of political leaders meaningfully addressing the intensifying climate problem is pitiful. A green energy transition is under way, but at too slow a pace to definitely stop far more heating.
Apocalyptic predictions or exaggerated diagnoses of today’s climate (“the world is on fire”) encourage fatalism or panic, both preventing planful action. Overall, the world has a lot to improve, but most geographies are on the way to meaningful CO2 reduction:
EDGAR — Emissions Database for Global Atmospheric Research
China stands out as the biggest polluter, but it still has the lowest emissions per capita — for whatever that’s worth. The United States is doing a lot to improve its energy mix, despite being the country where many people leave their cars idling and think of global warming as something that can be fought with air-conditioning.
And amazingly, renewable energy growth has been by far the highest in China where capacity growth from 2015 to 2020 has outpaced Europe’s and the US’s (496 GW vs. 184 GW vs. 133 GW, according to the IEA). China is seriously trying to get rid of its addiction to coal.
Here in the US, the two leading states for renewable energy production are Texas and Florida (about 12.6% of US total production), thereby demonstrating that attitude to climate change (skeptical) doesn’t always map with action.
The problem with global progress is that it’s all not enough to avert a dangerous rise in average temperatures that will most likely lead to significant structural changes in the composition of life on earth (putting it mildly):
A radical reduction of emissions in the short term, in a way that stops global warming, would require unimaginable changes to our economy (“degrowth”) which would be ultimately extremely harmful to the poorer part of humanity. Noah Smith has written an excellent piece about the fallacy of degrowth and argues convincingly that a decoupling of economic growth and emissions is a proven possibility. Many of our social ideas (the right to housing, jobs and education for everyone, healthcare) require economic growth, so does the prevention of climate-driven migration. Finally, we will need capital intensive technical progress in many forms to be successful in our combat against global warming — from renewables to CO2 extraction or even climate engineering.
It all depends on our willingness to accept the science behind the numbers and not dismiss it as a hoax. There is an inevitable degree of ambiguity in climate science and the predictions will keep changing as we improve. Most people don’t like ambiguity, so they choose the seemingly easy options (Ellsberg paradox), like doing nothing.
Our only plausible, evidence based, well researched and logically coherent theory is that global warming is caused by greenhouse gases, CO2 being the main culprit. As with any science, this is not 100% certain, but it’s currently the most likely explanation. Any other theory — and there are no other evidence based and logically coherent theories — is very unlikely to be true in this sense. But people try — i.e., an educated business friend of mine argued that the atmosphere’s CO2 concentration is only 4ppm and therefore negligible. In fact, it is 424ppm. And some intelligent people already predicted this over 100 years ago[xvi]:
[i] Cole, H. S. D. (1973). Models of doom; a critique of The limits to growth
[ii] https://www.nature.org/en-us/get-involved/how-to-help/carbon-footprint-calculator/carbon-by-birth-year/
[iii] https://www.ncei.noaa.gov/access/monitoring/climate-at-a-glance/global/time-series/nhem/land/1/7/1850-2023
[iv] Marcott, S.A., J.D. Shakun, P.U. Clark, and A.C. Mix. 2013. A reconstruction of regional and global temperature for the past 11,300 years. Science, Vol. 339. pp. 1198–1201. doi:10.1126/science.1228026. Shakun, J.D., P.U. Clark, F. He, S.A. Marcott, A.C. Mix, Z. Liu, B.L. Otto-Bliesner, A. Schmittner, A., and E. Bard. 2012. Global warming preceded by increasing carbon dioxide concentrations during the last deglaciation. Nature, Vol. 484, pp. 49–54. doi:10.1038/nature10915.
[v] Moberg, A., D.M. Sonechkin, K. Holmgren, N.M. Datsenko, and W. Karlén. 2005. Highly variable Northern Hemisphere temperatures reconstructed from low- and high-resolution proxy data. Nature, Vol. 433, pp. 613–617.
[vi] “How is climate change impacting the world’s oceans?” https://www.un.org/en/climatechange/science/climate-issues/ocean-impacts
[vii] A refugee is eligible for permanent resident status after living in the U.S. for one year. After five years of residence in the U.S. and gaining Permanent Resident Status, he or she may apply for citizenship. Refugees are admitted to the United States based upon an inability to return to their home countries because of a “well-founded fear of persecution” due to their race, membership in a particular social group, political opinion, religion, or national origin.
[viii] The numbers don’t include such immigrants who don’t become permanent residents, for whom the US provides up to 140,000 visa per year, and who are typically staying for a few years and then go back to their home country
[ix] Under the agreement, Mexico will continue to accept migrants from Venezuela, Haiti, Cuba and Nicaragua who are turned away at the border, and up to 100,000 individuals from Honduras, Guatemala, and El Salvador who have family in the U.S. will be eligible to live and work there. (AP News)
[x] The European Union is a clearly defined entity and excludes the UK. Europe is a historical and cultural concept that includes Turkey and has 750M inhabitants (according to Wikipedia). It used to include parts of Russia, but no more.
[xi] Declining birth rates since the 1960s have been closely linked to contraceptives. The lack of thereof in other countries (i.e., Niger) is the reason for higher birthrates, often based on religious mandates.
[xii] Marchofdimes.org and other sources
[xiii] i.e, Donald Trump: https://www.npr.org/sections/goatsandsoda/2018/01/12/577673191/trump-wishes-we-had-more-immigrants-from-norway-turns-out-we-once-did
[xiv] A common attitude in Northern Italy towards darker skinned Southern Italians, especially Sicilians, who were regarded as too close to Africans
[xv] “The scourge of climate doomism — The truth about global warming is bad enough. We don’t need harmful hyperbole” by Pilita Clark, Financial Times, August 15, 2023
[xvi] https://www.snopes.com/fact-check/1912-article-global-warming/
