Heat Tolerance of Some Animals Is Already Exceeded

Tiistai 19.4.2022 klo 20:22 - Mikko Nikinmaa

Among animals, humans are probably among the best in adapting to hot and arid environments. There are several reasons for this. First, we have lost the fur coat almost completely – thus the name “naked ape”. This maximizes the heat loss. Second, humans are able to use evaporative cooling better than virtually any animal. We have more sweat glands per unit area than other mammals, and the glands are of the eccrine type, whereas the glands of most other mammals are of apocrine type. Eccrine glands are capable of secreting sweat of low salinity for a long period of time. In contrast, the sweat form apocrine glands is of higher salinity, and the secretion capacity is smaller. Many mammals such as cats and dogs have limited number of sweat glands: they are completely absent in bats. Also in birds evaporative water loss is a major mechanism of cooling. This is often done by panting and in some species by gular vibration. The physiology of heat tolerance in small endotherms has been reviewed by McKechnie and Wolf in Physiology 34:302-313 (2019).

The problem with evaporative cooling is that it requires water, which is very scarce in arid environments. Thus, even in species such as humans, which have efficient evaporative heat loss, the lack of water may cause mortalities. As most hot areas also become drier, this is a major problem with climate change. That the heat-related problems have already become serious ones even to humans is given by the estimated increase in heat-related deaths, which has increased 20-fold in 20 years after 1990’s. For humans the mortality is small as compared to bats in Australia and in South Africa. As bats don’t have sweat glands, their tolerance of increased temperature is very weak. So heat waves have caused many bats to literally drop dead from the trees they have lived in. It is estimated that for one particular species 1/3 of the population has died because of the heat. In Australia and South Africa also mass mortalities of birds have occurred because of heat waves. I bet that similar heat-induced mass mortalities have taken place also in other hot, arid areas, but there have not been scientific reports about them. Also birds appear to have weaker tolerance of increased temperatures than mammals.

Any temperature increase now will put an increasing number of species to knife’s edge regarding their survival. Bats and birds serve as first indicators of intolerable heat. So, canary birds were used in coal mines as warning signs. Now birds indicate that coal use must be stopped. It is appropriate that the first mass mortalities of animals occurred in Australia as the country is the biggest coal exporter in the world.

Kommentoi kirjoitusta. Avainsanat: climate change, temperature regulation, mass mortalities, evaporative cooling

Physiological studies should be in the centre of climate change biology

Tiistai 12.4.2022 klo 15:49 - Mikko Nikinmaa

Climate change, and other environmental changes, affect the functions of organisms. The changes in populations and ecosystems follow these functional changes. If the functions of some organisms are not disturbed, the environmental change does not affect the ecosystem, if immigration and emigration can be accounted for.

These simple facts indicate that functional studies, i.e., physiology, should be in the centre of environmental biology. Indeed, a stone could have exactly the same molecules as an organism, but without functions it would still be a stone. However, physiological studies are marginalized in climate change research and environmental biology – there are less than 1/10th of published physiological articles as compared to ecological articles within environmental biology. Furthermore, studies on animals account for less than 1/3rd of the physiological studies.

In short, one carries out extensive ecological surveys and population genetic studies and observes that something has happened. This is the major problem with the research, it shows what has already occurred, but fails to evaluate why and how. With climate change research it is obvious that temperature increase plays a role, but only physiological studies can clarify, what the affected pathways are. Also, physiological investigations can answer in real time, if a disturbance is adequate to cause a perturbation in populations and ecosystems.

Climate change research as well as other environmental biology should be predictive. This requires that physiology becomes a central, not a marginal discipline. Studies require intensive, time-demanding work, which is often technically quite demanding. Because of this, the number of scientists working on physiological questions should be drastically increased. Only this makes it possible to turn environmental and climate change biology to predictive science, which is required to combat environmental problems.

Kommentoi kirjoitusta. Avainsanat: ecophysiology, ecology, environmental pollution, temperature

IPCC Report: an immense amount of information that climate change already affects the earth

Tiistai 1.3.2022 klo 19:06 - Mikko Nikinmaa

Another IPCC report has become available yesterday (February 28). They keep becoming larger, the full report now has 3685 pages. Its main findings are summarized in 35-page summary for policymakers. I am not going through the impressive amount of information, it can all be read at https://report.ipcc.ch/ar6wg2/index.html, but giving my musings about why this information is not accepted by almost a half of the people in industrialized countries. The publication of the IPCC report has been relegated to a secondary news item, because of the attack of Putin’s Russia to Ukraine, but the two have surprising links.

Russia’s main income is from oil and natural gas. Since the world is trying to diminish the use of fossil fuels, Russia’s incomes will be diminishing in future. Furthermore, since quite a few buildings have been built on permafrost, which is melting, there is a huge need for investments on new grounding of them. Together these facts mean that Putin saw his window of opportunity to restore the might of Russian empire to be now or never. I suppose he imagined that Ukraine could be easily conquered and puppet government installed there. That did not happen. He also supposed that Europe and NATO would be split. That did not happen, either. Rather, the unity of the Western World has increased, and resulted in so massive sanctions that Russian economy is reeling. This increases the economic problems that I alluded to above.

But, going to the climate deniers’ arguments. They are stating that government should decrease the price of fossil fuels and slow down the replacement of fossil fuels by carbon-free energy sources. Since already now the temperature increase is causing irreversible problems, the delay on the stop of fossil fuel use would cause increased climate-related problems. Besides, that would play in the hands of Putin regime, as it would increase the sales of natural gas and oil from Russia. In Finland, an argument is presented that one should continue the use of peat in the name of national fuel/energy security. However, peat can be equated to fossil fuels in the time range of climate change. Furthermore, the national energy production security can be obtained by wind power, because no foreign nation can stop the wind. Third, the climate deniers always say that there have always been changes in earth’s climate. This is naturally true, but the sheer speed of the change is unprecedent. In addition, predictable weather has actually enabled the development of present civilizations. Climate change is causing unpredictable heat waves, droughts, heavy rains and also cold spells in places they have seldom occurred.

Climate change already affects the lives of three billion people, and one of the most terrible things happening is the increase of sea level, which will affect a couple of billions more. One of the major points made in the IPCC report is that most of the predicted ill effects of climate change can still be avoided, but the actions against climate change need to be speeded up.


Kommentoi kirjoitusta. Avainsanat: fossil fuels, sea level, temperature, natural gas

How to avoid making friends in British Columbia?

Tiistai 16.11.2021 klo 13:40 - Mikko Nikinmaa

Climate change ain’t real.

Say that to anybody in British Columbia, if you want to be alone and disliked. First they had temperatures above 40oC in the summer, and now they have rain, which exceeds even their expectations. It has always rained a lot in BC in the autumn, but now the rains enough to cause flooding in an area known for its heavy autumn rains.

So when talking with British Columbians, start your conversation with the sentence above, if you do not want them to be your friends.

Kommentoi kirjoitusta. Avainsanat: climate change, floods, temperature

Functions Determine Temperature Effects on Animals and Man

Torstai 30.9.2021 klo 19:05 - Mikko Nikinmaa

Climate change is one of the most studied topics of the present time. The web of science contains approximately 350 000 scientific articles studying the topic. Out of these, around 64 000 have studied the biology of climate change. However, only about 1500 of those appear to be concerned with animal or human physiology. This is very concerning, since any effects of temperature changes must be a result of physiological responses to the change. All the other findings on animals and man will be downstream consequences of the physiological adjustments. In view of the above, the recent compilation of reviews in the Journal of Experimental Biology is very welcome. Since it is open access, everyone can read it at https://journals.biologists.com/jeb/issue/224/Suppl_1.

As an example, polar bears have become iconic victims of climate change. There are several documentaries about skinny and diseased creatures about to succumb to increased temperatures as they find less food, when sea ice decreases because of an increase in temperature. However, if that were the only problem they are facing, their plight would probably be tolerable. But since their food availability is decreased, they need to spend an increased amount of energy to catch the prey. Because of the sea ice loss, the energy needed for locomotor activity is 3-4 times higher than expected. Another problem with endotherms is that an increase in temperature is less well tolerated than a decrease. Further, an increase in temperature is a serious problem in dry environments because water loss increases.

For ectothermic animals, temperature increase causes various problems. Dive durations of reptiles, turtles and amphibians decrease by about a third. This translates directly to decreased feeding efficiency. The thermal niches of fish become decoupled from the light-dark rhythms, which function as cues for reproduction etc. When thinking about thermal niches, it appears that both tropical and polar fish tolerate changes in temperature less well than temperate ones. Two overall problems are apparent in translating most temperature studies on fish to climate change scenarios. First, the temperature changes due to climate change are usually much slower than temperature changes imposed on fish in experiments. Second, individual variation as an important component of temperature responses of fish is hardly ever considered. Also, one knows very poorly, what the actual physiological mechanisms behind the measures of thermal tolerance are.

The major reasons why our understanding of physiological mechanisms behind the responses to climate change are poor is due to the fact that functional studies have not been considered important. However, any ecological or genetic response can only occur, if physiological changes take place earlier. Thus, predicting climate change effects on animal populations requires understanding how animals respond physiologically, not by observing changes that have already occurred (either ecologically or genetically).



Kommentoi kirjoitusta. Avainsanat: climate change, physiology, temperature biology, individual variatio

Climate Change is the Reason for Texan Frost

Tiistai 14.9.2021 klo 16:11 - Mikko Nikinmaa

When it snows in Texas or Spain, the climate denialists rejoice saying that clearly climate change is only scare tactics of the climate believers. Hitherto it has been difficult to give explanations as to why climate change causes the cold spells in the south, heavy rains in Central Europe and extreme heat spells in the Arctic. However, two recent articles clarify the situation significantly, the ones by Osman et al in PNAS (PNAS September 21, 2021 118 (38) e2104105118; https://doi.org/10.1073/pnas.2104105118) and Cohen et al in Science (Science 3 Sep 2021, Vol 373, Issue 6559, pp. 1116-1121; DOI: 10.1126/science.abi9167). Below I try to summarize my understanding of the findings presented.

Much of the weather in North America and Europe is affected by North Atlantic Jetstream. The rains and heat spells depend on its position. With increasing mean temperature of the arctic it appears that North Atlantic Jetstream undulates more and its position shifts northwards as Arctic temperature increases. Southward undulations mean that cold air from the Arctic reaches more southern latitudes than earlier and northward undulations that southern hot air reaches north. Presently, changes in the general position of the North Atlantic Jetstream and its undulations are so variable that consistent weather changes do not occur – cold summer can follow a hot one and dry autumn a wet one. However, it can be predicted that by 2060 the jetstream has moved generally so much north that Southern Europe becomes consistently drier and Central Europe and Scandinavia wetter than currently.

The Arctic temperature increases more rapidly than temperatures elsewhere. This is called Arctic Amplification (AA). As a result of this general AA, it appears that mid-latitudes experience cooling of winters, as the still cold arctic air is able to stream to southern latitudes. This is the result of Stratospheric Polar Vortex stretching southwards, which may, in my opinion, coincide with the southward undulations of the North Atlantic Jetstream (where NAJ occurs). However, these are clearly independent in continental North America and Asia (where there is no NAJ). So, cold weather in southern areas can be a consequence of climate change.

In any case the predictability of weather patterns decreases markedly with climate change. As a consequence, agricultural production all over the world may be reduced, leading to increased problems for the mankind.

Kommentoi kirjoitusta. Avainsanat: temperature, winter, heat spells, drought

IPCC Report - Nothing New But Still Alarming: Immediate Global Climate Actions Are Needed

Tiistai 10.8.2021 klo 12:11 - Mikko Nikinmaa

The IPCC report on the physical science basis of climate change was released yesterday. It is not likely that many people read all its 1300 pages. However, it is enough if the 65-page summary for policymakers is read through. In fact, all of the findings and information are in line with what scientists have been saying for the past 50 years: ever since the book “Limits to Growth” was published in 1972. The scientists’ warning has been repeated twice – or three times, if you take into account the recent addition to the 2019 data. This is now the 6th IPCC report. The scientists’ voices have come louder and more demanding: actions are needed. What was a worst case possibility in 1970’s has become likelihood with high probability, if drastic actions are not done.

 With the wildfires raging throughout the world, many massive heat waves, heavy rains causing floods and droughts in various parts of the world one would think that people accept that climate change is taking place, and demands global action. Hot temperature extremes and heavy precipitation have increased frequency in most places, and there is not a single area in the world where their frequency would have decreased. Similarly, droughts have increased in many parts of the world, but decreased only in one: Northern Australia. Despite this, a significant proportion of people think that climate change is a hoax, and many politicians are of the opinion that one must not do any environmental actions if they interfere with economic growth and decrease the economic competitiveness.

Quite often those, who deny climate change, say that for example last year it snowed in Spain and Texas, and that very high temperatures have been reported earlier, e.g. in 1998. That one year is climate denials’ favourite, since having that as a basis, there has hardly been any change in average global temperature afterwards. However, it is known and repeatedly pointed out by climate scientists that natural variability dampens or accentuates changes in the short term. In fact, the probability of most types of extreme weather increases with climate change: the likelihood of both droughts and heavy precipitation doubles even if the temperature increase can be kept at 1.5oC; if drastic climate actions are not done, droughts become 5x more common, and heavy precipitation occurs 3x more frequently than now.

The climate problem is global. Thus, we cannot say that our country is doing its share, now the other nations should do the same. Combatting climate change in developing countries should be a primary focus of the rich countries, and rich individuals: what is the point of spending billions to military or space flights if the world is in peril. Even if the report is gloomy, we have all the technology and other means to still prevent the climate catastrophe. What is required is that we start to think globally instead of nationalistically.

Kommentoi kirjoitusta. Avainsanat: climate change, temperature, weather

It is not only American West

Torstai 1.7.2021 klo 18:58 - Mikko Nikinmaa

Cities in the Northwest of USA and Canada have had deadly heat. Temperatures above 40 C (more than 104 F) have been recorded in Portland, Seattle and Vancouver. It would be very hot even for San Diego, but those, up to now, cities with mild summer temperatures with heat waves being temperatures between 25 and 30 C really suffer. It would not be incredibly bad if one could say that this is an once in a thousand years occurrence in only one place in the Earth. However, one has had stationary heat wave reaching above the Arctic Circle in Siberia, with air temperature above 30 C and land surface temperature between 35-50 C.

In a way those temperatures are even worse than the heat wave in the American Northwest. Although many people do not live there, and thus the acute death toll caused by the high temperature remains small, it is permafrost area. As the permanently frozen soil (permafrost) melts, craters are formed, from which huge methane leaks enter the atmosphere. The gas is much worse greenhouse gas than carbon dioxide. 

Despite these huge changes, which occur in several places, and despite the years from 2000 to 2021 making up most of the years with globally highest temperatures, there still are people who deny climate change. Their attitude can be summarized by the following sentence: "Ok, world, which becomes uninhabitable because of heat, is the price we have to pay for having a growing economy."

The heat brings with it a couple of serious other problems. The agricultural areas in, e.g., California have serious lack of water, whereby crop yields start to decrease markedly. Further, wildfires probably increase in severity. Already in last year the Siberian forest fires caused more carbon dioxide release than was the whole decrease of carbon dioxide production in Europe.

The continuation of climate change is irritating, because we would have the means to stop it, and it could be done without serious harm to even us, the rich of the North. However, it would require changes in attitude, and that appears to be impossible. 

Kommentoi kirjoitusta. Avainsanat: climate change, heat wave, temperature anomaly

Cold winter and power failures - it is because fossil fuel industry and economic circles

Torstai 18.2.2021 klo 12:16 - Mikko Nikinmaa

A real winter throughout the Northern Hemisphere. Or actually worse that that. It has snowed in Madrid and the weather has been colder than ever in Texas. The climate change deniers say, pointing to this one incidence, how the whole concept is faulty. However, unexpected cold spells are something that is predicted based on an overall warming of the globe. The worming of the areas near the poles pushes the cold air south in the northern winter.

In Texas the energy production has stalled in most places. The Governor of Texas has claimed that this shows how green energy, wind and solar power, do not function when it is cold. As for many fossil fuel lobbyists, this is a lie. Out of the energy produced in Texas, wind and solar energy account for approximately 1/10. Energy is produced using mainly oil and natural gas. The reason for the huge power outages in the extreme cold was largely that the natural gas could not be pumped from the wells because of the extreme cold. That is actually due to the fossil fuel and economic lobbyists. If , instead of the need to pump natural gas from wells, there had been storage of the natural gas, energy could have been produced even in the cold. Now it was not possible. It was cheaper not to have natural gas storage, so since the likelihood of natural gas distribution because of extreme cold was not likely, storing was not done.

So the fossil fuel lobbyists claim that the problems they have themselves caused are caused by the environmentalists. The ways of oil industry remind me of how tobacco industry claimed for many years that tobacco didn’t cause any problems – against all scientific evidence. Now fossil fuel lobbyist are doing the same – lying against all the scientific evidence.

Kommentoi kirjoitusta. Avainsanat: climate change, fossil fuel, temperature

Hurricanes more long-lasting after landfall because of climate change?

Maanantai 16.11.2020 klo 13:23 - Mikko Nikinmaa

Hurricanes or typhoons – tropical cyclones cause immense damage because of the high-

Valimeri_2.jpgvelocity wind and heavy rain. A commonly accepted consequence of climate change is that the number of tropical cyclones per time period and their average strength increase both in North America and in East Asia. This is caused because the increase of oceanic temperature. Since the cyclones are fuelled by the moisture of air, and increased oceanic temperature increases air moisture above the ocean, the increased frequency and strength of hurricanes and typhoons is easy to understand.

Most of the damage is caused to coastal communities immediately after the landfall of the cyclones. Hurricanes weaken quite rapidly after the landfall, but a recent study in Nature (Li & Chakraborty, Nature 587, 230-247; 2020) suggests that hurricanes may weaken more slowly in a warmer climate. During the past fifty years the time taken for hurricane decay has virtually doubled. This appears to be due to the increase of moisture of the warmer air.

If hurricanes dissipate slower after landfall in warming climate, they cause damaga to larger areas than earlier. This adds to the need to increase actions against climate change. Even in fossil fuel energy were cheaper than renewable energy without taking into account the expenses caused in repairing hurricane damage, adding them to the costs would certainly stop fossil fuel use rapidly. Such climate tax could and should be added to the fossil fuel price at least in Europe, North America, Australia, Russia and China.

Kommentoi kirjoitusta. Avainsanat: temperature, fossil fuels, typhoon, tropical cyclones

The duo living in the past (Trump and Putin) are a major threat to sustainable life

Maanantai 19.10.2020 klo 17:50 - Mikko Nikinmaa

Both Putin and Trump are anchored in the past, and hope to make decisions on 50-year old premises. Nothing can hurt the environment and, consequently, our future more than living in the past. For Trump it is the days on glorious 1960’s America, sending man to the moon. Those days American cars were the envy of every European: they were big, lean and fast. Although they used twice as much petrol as the small European cars, it did not matter, there was plenty of oil to burn. At that time the fossil fuel industry, and other industries were firmly rooted in industrialized west. There was no globalization, China and even Japan were not any commercial competitor, and the world population was 2-3 000 000 000.

The world had two major powers, USA and Soviet Union. Putin still dreams that he is leading the great Soviet Union, which has always had czars. Until the time of 1917 revolution they were called czars, but Stalin and other ruthless leaders did not rule democratically. Communist Soviet Union considered environment only as a commodity for the benefit of the party. One could do whatever, change the direction of rivers, drain lakes etc. just as long as it helped the top officials of the party.IMG_20170807_0057.jpgdeeply rooted in the past. When Trump says the science does not know, if there is climate change, it is only one of his 20000 lies. There is more unequivocal evidence of anthropogenic influence on the state of the environment than for any other scientific endeavour. Climate change is taken seriously by all the American industries apart from the oil and coal industries. Even most of the energy sector sees that oil and coal belong to the past: the use of renewable sources has exceeded the use of oil and coal this year. So when Trump and Pence are talking about the excellent environmental record of the present government, they are telling lies, which even the commercial circles do not accept. It is almost worse with Putin, since he does not have any opposition. For him climate change is only an opportunity. Temperature increase will make the Arctic Ocean ice-free and navigable. As a result, the huge gas deposits of Siberia are easier to utilize than hitherto. It does not matter to him that the same temperature increase, which makes the Arctic Ocean ice-free, also causes permafrost thawing and liberation of immense methane deposits to the atmosphere. Since methane is much more powerful greenhouse gas than carbon dioxide, methane liberation may lead to vicious circle speeding up temperature increase even if humans tried to restrict greenhouse gas emissions elsewhere. Not that it matters to Putin, since he is of the opinion that even if there is climate change, it is not caused by human actions.

With these two science-denialists in power, it is all the more important that Europe steps up. Europe’s lead with backing from China and hopefully next year from USA will be needed. The only way to get Putin change his mind is to show that his fossil fuels cannot be marketed anywhere.

That’s what comes from living in the past – no decisions fitting the future.

Kommentoi kirjoitusta. Avainsanat: fossil fuels, climate change, temperature, Arctic Ocean, methane

Environmental effects are complex; that is the problem

Torstai 15.10.2020 klo 14:19 - Mikko Nikinmaa

In any natural environment all animals, here I am focusing on fish, experience changes in temperature, parasite infections etc. On top of that become all the anthropogenic contaminants, metals, pesticides, flame retardants, pharmaceuticals, personal care products and so on. The complex cocktail can affect organisms directly and indirectly, and a change in any variable can affect the growth, health and survival of them.gudgeon.jpg

Because it is very difficult to study, how the environmental heterogeneity and its changes affect animals, most studies use a defined set of abiotic conditions and one pollutant. While this gives much valuable information, it should be remembered that for example a change in temperature, oxygen level, age of animal, salinity of water and the presence of other contaminants can influence the observed result. Occasionally, one gets the surprising finding that what we think as a pollutant and thus expect a negative effect actually increases the tolerance to an environmental change. For example, when we studied the effects of oil pollution on the thermal tolerance of juvenile fish (rainbow trout and European sea bass), we observed that the oil-exposed fish, if anything, tolerated high temperature better than control specimens (Anttila et al 2017, Environ Sci Pollut Res DOI 10.1007/s11356-017-9609-x). Recently, Petitjean et al (Science of The Total Environment Volume 742, 10 November 2020, 140657) have studied gudgeons in six French rivers, and observed clear interactions between the metal loads and temperatures the fish experience: an increase of metal load at high temperature reduces growth. Naturally, this survey conducted in natural environment cannot differentiate between direct and indirect effects of metals. It remains as a possibility that, e.g., the prey organisms of the fish are affected initially, whereby their availability decreases, decreasing the growth of fish.

Here I have focused on temperature, because we are currently undergoing a giant-scale natural event, climate change. It would be much simpler to evaluate, how temperature increase as such affects living functions, than take into account how temperature change affects responses to the mixture of environmental contaminants. The temperature effects can be completely opposite for different contaminants.

Kommentoi kirjoitusta. Avainsanat: climate change, environmental pollution, toxicant, cocktail effects, fish, temperature

It is getting hot in Death Valley

Tiistai 18.8.2020 klo 17:26 - Mikko Nikinmaa

In early spring 1983 Death Valley was a pleasant place to visit. The annual rains were over and where water had flown just weeks earlier was now a stream of flowers. Where there still was water, it was so salty that salt started to crystallize on the strands of the small creeks. The creeks were full of small fish. which needed to reproduce before the disappearance of water. The temperature was about +30oC during the day and dropped to about +20 in the night.

IMG_20170725_0042.jpgI could not but think of those pleasant memories from about 40 years ago, when I read the news. The temperature in Death Valley had reached an all-time high, about +55 oC in shade. We Finns, who enjoy sauna at temperatures around +90 oC would call that Swedish sauna. However, even though we like our saunas much hotter than the recorded Death Valley temperature, it would not be possible to spend long periods of time in temperatures above +50 oC. Although there was a recent report that many more people die because of too low than too high temperature, saying that thus climate change-induced increase in mean temperature generally is beneficial to humans, promoting their survival, that doesn’t take into account many physiological effects on humans. Further, the general effects on animal and plant life are devastating.

Even if people die of cold, death does not occur, if clothing can be increased. In contrast, humans cannot live at temperatures above +50oC. One soon becomes dehydrated and it is not possible to drink adequate amount of water to prevent dehydration. The reason for dehydration is that humans try to regulate body temperature. If it increases above +42oC, the function of some vital proteins is affected so much that death ensues. The body temperature increases to a deadly level, if ambient temperature remains above +50oC for a day or two. The only way to avoid death is to use much energy in air conditioning, which is not possible in poor areas, and which contributes to the temperature increase with the present technology. The extremely high temperatures are not restricted to Death Valley, but similar shade temperatures have been recorded in Iran. In Australia and Southern Europe summer temperature above +40 are common and London recently recorded an all-time high of six days above +34oC. Even in Alaska temperatures above +30 have become common.

While the high temperatures are uncomfortable to humans, who can resort to air conditioning, they are deadly to wild animals, which do not have that alternative. Also, as I wrote in my previous blog, temperature increase will have huge adverse effect on fish stocks, which are envisioned to be a major protein source for humans in future. Further, plant growth is reduced drastically – it is simply too hot and enough moisture cannot be delivered for plant growth – it is no surprise that all the world’s hottest places are desert.

The temperatures reached all around the world indicate unequivocally that climate change is no fiction, and show that without drastic measures a large part of the planet can become uninhabitable. However, there is a silver lining to the Covid-19 pandemic. It has shown that drastic measures can be taken in most places. If climate change were considered to be a similar threat, which it certainly is (or much worse), then it would clear that actions much beyond Paris Treaty would be taken. And it is possible.

Kommentoi kirjoitusta. Avainsanat: climate change, temperature

From Concrete to Wood in Building: Combatting Climate Change

Keskiviikko 18.12.2019 klo 14:53 - Mikko Nikinmaa

Another indication of the climate change is the observation that Australia experienced the hottest day ever. Despite this and a multitude of other signs, the backward-looking politicians like the Australian prime minister thwart any actions to combat climate change. President Trump lists as one of his major achievements “cancellation of the unfair and costly Paris Climate Agreement”.

The discussion about climate change has concentrated on coal and oil use in energy production and on eating meat. Also flying and rain forests have attracted much media attention. It is seldom mentioned that the size of the human populIMG_20170809_0038.jpgation is a problem, and actually makes the populistic solution of going back to the past impossible. In the past that the backward-looking leaders want to return to, there were two-three billion people, now we are about eight billion. With two-three billion people, limits to growth had not been reached, now they have. The importance of unicellular algae of the ocean in generating the oxygen balance by photosynthesis is often not acknowledged. Yet, almost half of the oxygen-generating photosynthesis is carried out by these small algae. Finally, one of the important carbon dioxide sources is concrete building – it accounts close to ten percent of the present carbon dioxide emissions.

Thus, one should stop building using concrete and steel. Most of the carbon dioxide emissions are due to cement production, an indispensable component of concrete. Making brick or stone houses would already be much better than concrete. However, the pest alternative would be wooden houses. Technologies are already available, which enable building multi-store houses. Further, the probability of burning of wooden houses is much reduced from 19th century, when whole cities could burn. In a wooden house the carbon would be stored for its entire life length, up to several hundred years. Thus, if all new buildings were wood-based, the carbon footprint of building sector would decrease for 10 % of world total to 0. This would be a huge win in combatting climate change, and could be reached with the presently available techniques. In view of this, one must ask: why is it not done?

Kommentoi kirjoitusta. Avainsanat: carbon footprint, population growth, Paris Climate Agreement, temperature

Nobel Prize for Oxygen Sensing and Hypoxia: the Environmental Relevance of Phenomena

Tiistai 8.10.2019 klo 9:37 - Mikko Nikinmaa

One of the most conspicuous changes that occur in the aquatic environment is the increasing occurrence of hypoxic areas. The Nobel Prize in Physiology and Medicine is this year given to three scientists, Kaelin, Ratcliffe and Semenza, who have studied and discovered the mechanism of how oxygen deficiency controls gene expression in man. Compared to air-breathers, fish and other aquatic animals must get by with 1/30th of the oxygen concentration. They are further faced with marked variations in oxygen level both daily and seasonally (or unknown periods of time). Further, since fish are poikilothermic, temperature changes affect their oxygen requirements conspicuously.

The oxygen sensing and transport system of fish must therefore be more vHIF.bmpersatile than that of mammals. We have studied the oxygen sensing and hypoxia-inducible factor (HIF) system, i.e. the phenomena now awarded Nobel Prize, since the late 1990’s. First, we observed that hypoxia-inducible factor was present in cells already in normal venous oxygen tension, although it increased in hypoxia (in humans and laboratory rodents it is only found in hypoxic conditions). Second, we observed that although the hypoxia-inducible factor level was controlled posttranscriptionally, also gene transcription could be modified. The HIF transcription depended on the number of hypoxic bouts experienced by the animal (in humans the control of HIF level occurs posttranscriptionally). Finally, we observed that HIF level was affected by temperature (something that is irrelevant for us homeotherms). These facts, together with the observations of interactions between HIF and circadian rhythms and environmental pollutants show that the system given the Nobel Prize for is more versatile in poikilothermic water breathers than humans.

Given that oxygen is a limiting factor in aquatic environment, it is no surprise that HIF system in fish has evolved differently in different fish groups depending on their oxygen requirements. In continuation, the possibilities of fish to adapt to climate change and environmental pollution are markedly affected by what their HIF system is. Thus, the Nobel Prize winning studies have a significant environmental angle. This has been reviewed to some extent in Nikinmaa, M. and Rees, B.B. (2005) Oxygen-dependent gene expression in fishes. Am. J. Physiol. - Regul. Integr. Comp. Physiol. 288, 1079-1090 and in Prokkola, JM and Nikinmaa M (2018) Circadian rhythms and environmental disturbances - underexplored interactions. J. Exp. Biol. 221, jeb179267. The evolution of HIF system in animals was explored in Rytkönen KT et al (2011) Molecular Evolution of the Metazoan PHD–HIF Oxygen-Sensing System. Mol. Biol. Evol. 28: 1913-1926.

Kommentoi kirjoitusta. Avainsanat: climate change, temperature, hypoxia, evolution, environmental pollution

Iron availability limits well-being of fish in open oceans?

Maanantai 16.9.2019 klo 11:46 - Mikko Nikinmaa

Iron is essential for production of haemoglobin and many enzymes (e.g. cytochromes, which include most detoxification enzymes). It is known that iron availability is very low in some parts of the open ocean, notably the Southern Seas, areas around Antarctica. It is also known that iron availability limits phytoplankton growth in the oceans. A recent article in Frontiers in Marine Science (Galbraith et al (2019) Growth Limitation of Marine Fish by Low Iron Availability in the Open Ocean. Frontiers Mar Sci 6:509) argues quite convincingly that this may be the case also for fish. One of the good points made by the authors is that the icefish without haemoglobin have only evolved in the iron-poor waters of Antarctica, not in the much iron-richer Arctic waters, although the temperatures in both are the same, and the low temperature is usually used as the reason for the possibility to the evolution of icefish devoid of haemoglobin. If the evolution has been just a random event, the question remains: why has not this random event taken place in the Arctic? Now, because the low temperature allows it, the haemoglobinless icefish benefits immensely from not having to produce haemoglobin. Compared to fish with haemoglobin, its iron requirements are about 20 times smaller, enabling it to live comfortably in iron-poor environment.

If iron availability limits the well-being of fish, it also causes problems with pollutants requiring cytochrome-dependent detoxification. Usually the detoxification system produces more cytochromes upon toxic insults. However, this may be difficult or impossible for species living in iron-poor areas. If this is the case, pollution of the Southern Seas may be a much more serious for fish inhabiting the area than, e.g. for fish living in North Atlantic.

Kommentoi kirjoitusta. Avainsanat: environmental pollution, icefsh, low temperature

Positive Feedbacks Accelerating Climate Change - Unless We Stop Anthropogenic Influence

Maanantai 29.7.2019 klo 16:01 - Mikko Nikinmaa

even if human effects were only a small proportion of factors causing temperature increase (which they are not, but I am saying it this way to make even people who deny a major influence of anthropogenic effects on temperature increase to understand the need to do everything possible to prevent any human effect), there are three things, which accelerate temperature increase, if temperature increases enough to start to cause them. And since they are possibly already happening, we should do our utmost that the human influence on temperature is mitigated.

First, as I have written in this blog a couple of times, if permafrost startsIMG_0401.JPG melting, methane deposits underneath it reach the atmosphere. Since methane is more than 20 times more effective greenhouse gas than carbon dioxide, the release of methane to the atmosphere radically increases the temperature.

Second, temperature increase makes forest fires more likely. There are presently massive forest fires in Siberia and Alaska, which are producing as much carbon dioxide as Sweden in a year. Notably, one of the most common reasons causing forest fires is that cigarette butts are thrown to the environment. Fire need not start at once, but may begin, when suitable winds come.

Third, if the sea ice melts, the heat radiation is not reflected back, but absorbed by the much darker water. We can see this every year, when snow melts. Melting proceeds slowly as long as there is no dark spot anywhere, but as soon as bare ground is exposed anywhere, melting speeds up.

Because of these absolutely natural factors will speed up the temperature increase radically, it is important that even if human influence on temperature is deemed small, it is stopped without saying “doing it will decrease our economic competitiveness”. The failure to do what we can do may be the needle that breaks the camel’s back – small factor in itself, but added to everything else the reason for the generation of vicious circle.

Kommentoi kirjoitusta. Avainsanat: temperature, forest fires, methane, sea ice

Sweating in the Heat Wave - the New Normal

Perjantai 26.7.2019 klo 12:37 - Mikko Nikinmaa

All time temperature records have been broken is Europe. When the high temperatures should be around 20 Celcius in Alaska, they have been about 30. High temperature records have been broken in East Coast and Midwest of USA. India has suffered from the worst heat waves ever. July of 2019 will probably become the warmest July in the world during measured history. And among the ten highest average temperatures of the year, nine are from the years 2010-2018. Yet there are people denying that climate change is occurring. Another group is saying that tAutiomaa.jpghere may be temperature increase, but that it does not have anything to do with human actions. I cannot understand either: statistics show the temperature increase. And if one is of the opinion that there may be temperature increase, but that it is not anthropogenic, why would one oppose climate change actions. If the actions were successful in decreasing carbon dioxide (and methane) levels, but still the temperature would increase, the persons could say "what did I say".

The temperature increase has already caused deaths of animals. Last summer there were a lot of fish kills in small Finnish lakes, which could only be attributed to temperature increase. Similarly, in marine Australian waters temperate fish species have experienced significant mortalities while tropical fish have had no ill effects. The four-horned sculpin in the Baltic Sea has all but disappeared. While the reason for its population decrease has not unequivocally been clarified, it is worth noting tha it is a cold-water species and has disappeared during the time that temperature has increased by 3 degrees.

Although it is probably useless to say these things to the readers of this blog, since undoubtedly you all agree with the above points, I am at a loss in trying to make climate sceptics to realize that something should be done, and fast.

Kommentoi kirjoitusta. Avainsanat: climate change, climate sceptics, temperature

No Anthropogenic Climate Change? Another case where correlation is falsely interpreted to indicate causality

Lauantai 20.7.2019 klo 15:05 - Mikko Nikinmaa

An article “giving experimental evidence” that it is not greenhouse gases, but changes in humidity/low level clouds, causing temperature increase, is circulating. The article is widely used by climate sceptics to indicate that carbon dioxide increase has little to do with the observed temperature increase. I wish it were so, but a quick reading of the ArXiv 2019 (Kauppinen & Malmi; arxiv.com) manuscript (NO EXPERIMENTAL EVIDENCE FOR THE SIGNIFICANT ANTHROPOGENIC CLIMATE CHANGE) indicates a serious problem in the conclusion. Measurements of temperature change are unequivocal – temperature has increased markedly from preindustrial time, especially during the last 50 years. Since temperature, cloud cover and humidity data can be found, the authors have calculated correlations between temperature and the other two and have shown significant IMG_3885.jpgrelationship. Up to this point I have no quarrel with the authors. But then, at least to my understanding, they conclude that these correlations indicate causality. From the observed temperature and cloud cover change they calculate that an increase in % cloud cover causes a decrease in temperature by 0.11 degrees/% cloud cover. However, correlation does not mean causality, it is equally possible that an additional factor influences one or both components of the correlation. A good example of this is the classical ice cream eating and drowning-relationship. There is very tight correlation between the consumption of ice cream and the number of drowning accidents. Yet, few people would claim that ice cream eating causes drowning. A similar problem is in this case, the authors’ calculation indicates an association between cloud cover change and temperature increase. However, the reason why the temperature increases is not verified by the authors’ calculations. It could be anything, for example anthropogenic. Thus, the study does not prove “that the changes in the low cloud cover fraction practically control the global temperature”. It is difficult for me to understand, why this kind of obvious weakness has remained unobserved, when at the same time inaccuracies in the IPCC conclusions are pointed out.

Kommentoi kirjoitusta. Avainsanat: global temperature, climate sceptics, cloud cover, anthropogenic

A vicious circle is functioning already? Warming liberates methane and methane causes warming

Perjantai 18.1.2019 klo 20:26

Methane is about 20 times as effective in causing climate warming as carbon dioxide. Much of the methane is in deposits under permafrost in the Arctic areas. Recently, another source under the permanent ice in Greenland has become apparent. The estimations of atmospheric methane level indicate that the amount liberated from agricultural sources, ruminants and swine, industrial sources, and waste treatment is not enough to explain the measured level in the last years. This means that the Arctic deposits are already contributing to the level. Notably, people visiting permafrost areas have reported that small craters can be found in permafrost, suggesting that underground methane has escaped in those places. Also, the ice cover in Greenland has been melting with simultaneous liberation of methane.

The possibility of getting close to temperature increase, which generates vicious methane cycle; methane causes temperature increase which liberates methane, is demanding that climate actions restrict temperature increase to the 1.5-2 degrees agreed in the Paris Climate Accord. By doing this, it is probably possible to prevent entering the vicious circle. However, it is most likely not possible to do it cheaply, so that the "climate promises" of different political and economic circles, which say that we do climate actions as long as they do not disturb economic growth, are utter nonsense. If real climate asctions were the goal, growthnideology would be scrapped, and the high-GNP countries would dacrease their "standard of living" to half to enable funding of climate actions to be able to avoid entering the vicious methane circle.

Kommentoi kirjoitusta. Avainsanat: climate change, natural gas, temperature, permafrost

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