<p>I would say that the reason is because human civilisation, and particularly agricultural practices, evolved and are adapted to the pre-industrial climate.  This means that any substantial change in the climate will require changes in our civilisation and agriculture, which inevitably has a cost.  So the reason that most of the changes are negative is not to do with the science, but to do with us.</p>

CC BY-SA 4.0
2020-01-15T23:48:09.470Z
Not just human society (broader than just civilisation). AGW induced climate change is already seriously impacting many, many other species, and even entire ecosystems. The reasons are the same that you have given - evolution is a matter of adaptation to prevailing conditions. Conditions change => evolutionary fitness to prevailing conditions decreases *more often than not* (e.g. it can be beneficial for some species in some situations, but the average impact will be negative). All human societies rely on non-human ecosystems to some extent too, so there are flow-on effects back to us.
naught101
CC BY-SA 4.0
2020-01-15T09:59:39.217Z
2020-01-15T09:59:39.217Z
Dikran Marsupial
<p>I don't think there are any effects of climate change, which can be said to be particularly positive.</p>

<p>The level of CO2 in the atmosphere we're currently experiencing has not been seen on earth for about 800,000 years <a href="https://www.ipcc.ch/site/assets/uploads/2018/02/WG1AR5_SPM_FINAL.pdf" rel="nofollow noreferrer">IPCC AR5</a> and the consequences of this change in radiative forcing are massive. Particularly as we've engineered this change in the last 150 years or so (ridiculously fast as far as natural systems are concerned). The change is extremely large in magnitude and speed - and this is going to have a huge impact - so I think you're right in that pretty much any change is bad change. My best shot at some positive human results are</p>

<p>1) an ice-free northwest passage round the top of Canada and</p>

<p>2) a marginal improvement in the UK for agriculture</p>

<p>These are of course completely outweighed by the other costs - in both human and natural systems. </p>

CC BY-SA 4.0
2020-01-07T18:48:15.820Z
It is an anthropocentric point of view. Thermophile organisms might have a different opinion! (just kidding)
Jean-Marie Prival
CC BY-SA 4.0
2020-01-08T08:45:13.403Z
Fair point! I guess it's possible that some form of algae or bacteria will do very well out of it - and rats and mosquitoes seem to like everything we do. I'd argue that this is outweighed by the catastrophic damage to other organisms though...
Will
CC BY-SA 4.0
2020-01-08T10:36:56.127Z
Positive effects? In UK thousands of old folk are speeded on their way to the promised land by hard winters, so milder winters will save thousands of lives. Another beneficial effect is that the N.W and NE Passages will be opened up to shipping, enabling them to take short cuts to their destinations, use less fuel and thus cut CO2 emissions. Another benefit, provided the heating doesn't go too far, is that warm climates have greater biodiversity than cold climates. Of course, that means cold-loving species like Gyrfalcons and Ptarmigan will be pushed further north or onto higher ground.
Michael Walsby
CC BY-SA 4.0
2020-01-10T10:53:49.567Z
@MichaelWalsby Please post answers as answers, not as comments.
gerrit
CC BY-SA 4.0
2020-01-10T11:48:26.507Z
I can think of a lot of locally-positive effects, and lots of locally-negative effects. All else being equal I imagine that the negative would outweigh the positive, simply because there's more land at low latitude (hot places) than there is at high latitudes (cold places that might benefit). Not sure how valid that rather simplistic analysis is ;-) The net effect is modulated by the speed, and hence that it isn't pain free (to say the least) for populations to move.

And of course things like ocean acidification are global negatives.
Semidiurnal Simon
CC BY-SA 4.0
2020-01-07T18:20:23.693Z
2020-01-07T18:20:23.693Z
Will
<p>If you consider what climate is -- the typical range of temperatures, precipitation, and other meteorological conditions that a region experiences -- and the fact that both nature and human society and civilization have adapted to the regional climates across the globe, then you can see that any substantial and relatively rapid change is likely to have what we would perceive as negative effects.</p>

<p>This is just a broad illustration, but for example, there's a vast swath of the north hemisphere suitable for growing wheat because of a combination of soil quality, available precipitation, and growing degree days (crop heat units). Farms, cities, roads, and other infrastructure have been built around this cropland for generations to take optimal advantage of existing conditions and reduce costs for delivering the wheat to market. More crop heat units can make a region more productive, but daily temperatures above 82 degrees will start stressing and killing the plants. Even if land closer to the poles becomes more farmable -- no guarantee -- simply changing what can be brown at a given latitude can reduce a nation's ability to feed itself.</p>

<p>There are other ways in which human civilization has adapted to current regional conditions: Communities rely on air conditioning in the summer and/or heating in the winter to make regions tolerable. Harbors and coastal communities are built to suit current sea levels. In general, increased temperatures will make warmer regions less tolerable and more expensive to live in (<a href="https://www.nature.com/articles/s41467-019-10399-3" rel="nofollow noreferrer">through cooling and similar costs</a>) and <a href="https://www.yaleclimateconnections.org/2019/06/heat-waves-and-climate-change-is-there-a-connection/" rel="nofollow noreferrer">more prone to deadly heat waves</a>, while potentially making colder regions more tolerable and less expensive (through reduced heating costs). Similarly, dramatic cooling would also affect where everything grows, reduce growing degree days for growing plants, and making colder regions less tolerable and more costly.</p>

<p>While attempting to quantify the "<a href="https://www.nature.com/articles/s41558-018-0282-y.epdf?author_access_token=XLBRLEGdT_Kv0n8_OnvpedRgN0jAjWel9jnR3ZoTv0Ms70oz073vBeHQkQJXsJbey6vjdAHHSPxkHEN8nflPeQI6U86-MxWO1T1uUiSvN2A-srp5G9s7YwGWt6-cuKn2e83mvZEpXG3r-J0nv0gYuA%3D%3D" rel="nofollow noreferrer">Country-level social cost of carbon</a>," a 2018 study in <em>Nature Climate Change</em> by Kate Ricke, et. al. assessed the net economic impact on individual countries and concluded that the costs are "unevenly distributed": "Countries that incur large fractions of the global cost consistently include India, China, Saudi Arabia and the United States."</p>

<p>Northern countries such as Russia, Canada, Norway, Sweden, the United Kingdom, France, Germany, and Poland actually receive a slight direct benefit from climate change through factors such as reduced heating costs.</p>

CC BY-SA 4.0
2020-01-12T02:30:22.180Z
2020-01-12T02:30:22.180Z
jeffronicus
<p>Much has been said about the negative effects, but there are positive effects as well. In UK thousands of old folk are speeded on their way to the promised land by hard winters, so milder winters will save thousands of lives. Excessively hot summers can also cost lives, but in UK those killed by cold weather greatly outnumber those killed by heat waves. Another beneficial effect is that the NW and NE Passages will be opened up to shipping, enabling ships to take short cuts to their destinations, use less fuel and thus cut CO2 emissions. Another benefit, provided the heating doesn't go too far, is that warm climates have greater biodiversity than cold climates. Of course, that means that cold-loving species like Gyrfalcons and Ptarmigan will be pushed further north or onto higher ground (Gyrs have never bred in Britain,Ptarmigan do,and Snowy Owls occasionally). A number of new species including Little Egrets and Cattle Egrets are already colonising the south of UK.</p>

<p>A cooler climate would also have both positive and negative effects, but we are not likely to get that for some considerable time.</p>

CC BY-SA 4.0
2020-01-10T15:50:51.080Z
I live in England , so I should know, and I've lived here for a very long while. It.s not the averages that kill people, but the below average temperatures. In Shropshire, 1982, the temperature was -26C.
Michael Walsby
CC BY-SA 4.0
2020-01-10T17:21:59.323Z
Th4ere are more species in a square mile of tropical rainforest than on the entire Antarctic continent.
Michael Walsby
CC BY-SA 4.0
2020-01-10T21:10:17.017Z
@ebv England doesn't have what other countries would recognise as cold winters, but it also has phenomenally poor housing stock. Without checking, I suspect Michael's probably right that cold kills more than heat at the moment. It'll change.
Semidiurnal Simon
CC BY-SA 4.0
2020-01-15T23:55:06.457Z
"warm climates have greater biodiversity than cold climates" is not strictly true. Biodiversity is highly dependent on water and nutrient availability. See figure 3 of https://www.researchgate.net/publication/215672861_Patterns_of_vascular_plant_diversity_at_continental_to_global_scale/figures for example. Deserts in the tropics have low biodiversity. Also, biodiversity will not necessarily increase in temperate zones with warming - many locally adapted species will die off, and only some species from warmer regions will invade. Speciation is not likely to have major impacts in the short term.
naught101
CC BY-SA 4.0
2020-01-16T10:26:26.247Z
I knew somebody would raise the objection that it isn't true of deserts, but I was stating a general principle. There are more species in one square mile of tropical rainforest than on the entire Antarctic continent. If there is one thing I know an enormous amount about it is the world's wildlife in general and UK wildlife in particular. You are only telling me what I already know.
Michael Walsby
CC BY-SA 4.0
2020-01-10T15:01:20.187Z
2020-01-10T15:01:20.187Z
Michael Walsby
<p>Most of the commonly mentioned effects of the ongoing and predicted climate change are negative: more extreme weather effects, more destructive weather, more diseases, rapid extinctions, etc.</p>

<p>Why is this so?</p>

<p>It is clear that <em>any rapid change</em> brings many negative effects. We humans, as well as the biosphere, are adapted to the current conditions. Any sudden deviation from these conditions will take painful re-adaptation.</p>

<p>But my impression is that several of the commonly mentioned negative effects go beyond than what can be explained by just <em>change</em>. Is this really so?  If yes, would a cooling climate (beyond restoring pre-industrial conditions) bring more positive effects?</p>

CC BY-SA 4.0
2020-01-06T13:47:41.880Z
This is, unfortunately, a highly politically charged topic which makes it hard to find reliable information on the web. A typical web search results mostly in articles that are emotionally charged, politically motivated, simple opinion from a random person with no qualifications, or just too dumbed down. My question is an honest one, and I hope it will get a reasonable answer here.
Moose
CC BY-SA 4.0
2020-01-06T13:57:05.253Z
A added the word "predicted" to clarify that I am referring to the one in the present time, not any other one during the history of the Earth. Feel free to phrase it better and edit.
Moose
CC BY-SA 4.0
2020-01-06T20:03:38.337Z
What effects do you think don't fall in to the "change" category.
John
CC BY-SA 4.0
2020-01-07T09:16:41.910Z
@John For example, more extreme weather events.
Moose
CC BY-SA 4.0
2020-01-07T12:57:31.620Z
her is an easy one, how powerful a weather event can be is controlled by how much energy there is in the system, heat is energy, so the warmer the climate the more energy there is to power weather systems so yes cooling reduce these effects.
John
CC BY-SA 4.0
2020-01-08T01:52:36.953Z
If you mean economic, you can find [maps of the +/- impacts](https://www.google.com/search?q=climate+change+gdp&client=ubuntu&hs=A1i&channel=fs&source=lnms&tbm=isch).
Keith McClary
CC BY-SA 4.0
2020-01-10T16:25:36.987Z
*Most of the commonly* **mentioned** *effects* -> because in the media, negative things are usually considered more newsworthy. And that could be justified because it has larger consequences.
Jan Doggen
<climate-change>
Why are most effects of the predicted climate change negative?
Moose
# Why are most effects of the predicted climate change negative?

(Asked by: username_0 on 2020-01-06)

Most of the commonly mentioned effects of the ongoing and predicted climate change are negative: more extreme weather effects, more destructive weather, more diseases, rapid extinctions, etc.

Why is this so?

It is clear that *any rapid change* brings many negative effects. We humans, as well as the biosphere, are adapted to the current conditions. Any sudden deviation from these conditions username_6 take painful re-adaptation.

But my impression is that several of the commonly mentioned negative effects go beyond than what can be explained by just *change*. Is this really so? If yes, would a cooling climate (beyond restoring pre-industrial conditions) bring more positive effects?

**Tags:** climate-change

> **Comments:**
> **username_0**: This is, unfortunately, a highly politically charged topic which makes it hard to find reliable information on the web. A typical web search results mostly in articles that are emotionally charged, politically motivated, simple opinion from a random person with no qualifications, or just too dumbed down. My question is an honest one, and I hope it username_6 get a reasonable answer here.  
> **username_0**: A added the word "predicted" to clarify that I am referring to the one in the present time, not any other one during the history of the Earth. Feel free to phrase it better and edit.  
> **username_1**: What effects do you think don't fall in to the "change" category.  
> **username_0**: @username_1 For example, more extreme weather events.  
> **username_1**: her is an easy one, how powerful a weather event can be is controlled by how much energy there is in the system, heat is energy, so the warmer the climate the more energy there is to power weather systems so yes cooling reduce these effects.  
> **username_2**: If you mean economic, you can find [maps of the +/- impacts](https://www.google.com/search?q=climate+change+gdp&client=ubuntu&hs=A1i&channel=fs&source=lnms&tbm=isch).  
> **username_3**: *Most of the commonly* **mentioned** *effects* -> because in the media, negative things are usually considered more newsworthy. And that could be justified because it has larger consequences.  

---

## 4 answers

### Answer by username_4 on 2020-01-15. Score: 3

I would say that the reason is because human civilisation, and particularly agricultural practices, evolved and are adapted to the pre-industrial climate. This means that any substantial change in the climate username_6 require changes in our civilisation and agriculture, which inevitably has a cost. So the reason that most of the changes are negative is not to do with the science, but to do with us.

> **Comments:**
> **username_5**: Not just human society (broader than just civilisation). AGW induced climate change is already seriously impacting many, many other species, and even entire ecosystems. The reasons are the same that you have given - evolution is a matter of adaptation to prevailing conditions. Conditions change => evolutionary fitness to prevailing conditions decreases *more often than not* (e.g. it can be beneficial for some species in some situations, but the average impact username_6 be negative). All human societies rely on non-human ecosystems to some extent too, so there are flow-on effects back to us.  

---

### Answer by username_6 on 2020-01-07. Score: 1

I don't think there are any effects of climate change, which can be said to be particularly positive.

The level of CO2 in the atmosphere we're currently experiencing has not been seen on earth for about 800,000 years [IPCC AR5](https://www.ipcc.ch/site/assets/uploads/2018/02/WG1AR5_SPM_FINAL.pdf) and the consequences of this change in radiative forcing are massive. Particularly as we've engineered this change in the last 150 years or so (ridiculously fast as far as natural systems are concerned). The change is extremely large in magnitude and speed - and this is going to have a huge impact - so I think you're right in that pretty much any change is bad change. My best shot at some positive human results are

1) an ice-free northwest passage round the top of Canada and

2) a marginal improvement in the UK for agriculture

These are of course completely outweighed by the other costs - in both human and natural systems.

> **Comments:**
> **username_7**: It is an anthropocentric point of view. Thermophile organisms might have a different opinion! (just kidding)  
> **username_6**: Fair point! I guess it's possible that some form of algae or bacteria username_6 do very well out of it - and rats and mosquitoes seem to like everything we do. I'd argue that this is outweighed by the catastrophic damage to other organisms though...  
> **username_8**: Positive effects? In UK thousands of old folk are speeded on their way to the promised land by hard winters, so milder winters username_6 save thousands of lives. Another beneficial effect is that the N.W and NE Passages username_6 be opened up to shipping, enabling them to take short cuts to their destinations, use less fuel and thus cut CO2 emissions. Another benefit, provided the heating doesn't go too far, is that warm climates have greater biodiversity than cold climates. Of course, that means cold-loving species like Gyrfalcons and Ptarmigan username_6 be pushed further north or onto higher ground.  
> **username_9**: @username_8 Please post answers as answers, not as comments.  
> **username_10**: I can think of a lot of locally-positive effects, and lots of locally-negative effects. All else being equal I imagine that the negative would outweigh the positive, simply because there's more land at low latitude (hot places) than there is at high latitudes (cold places that might benefit). Not sure how valid that rather simplistic analysis is ;-) The net effect is modulated by the speed, and hence that it isn't pain free (to say the least) for populations to move.  And of course things like ocean acidification are global negatives.  

---

### Answer by username_11 on 2020-01-12. Score: 0

If you consider what climate is -- the typical range of temperatures, precipitation, and other meteorological conditions that a region experiences -- and the fact that both nature and human society and civilization have adapted to the regional climates across the globe, then you can see that any substantial and relatively rapid change is likely to have what we would perceive as negative effects.

This is just a broad illustration, but for example, there's a vast swath of the north hemisphere suitable for growing wheat because of a combination of soil quality, available precipitation, and growing degree days (crop heat units). Farms, cities, roads, and other infrastructure have been built around this cropland for generations to take optimal advantage of existing conditions and reduce costs for delivering the wheat to market. More crop heat units can make a region more productive, but daily temperatures above 82 degrees username_6 start stressing and killing the plants. Even if land closer to the poles becomes more farmable -- no guarantee -- simply changing what can be brown at a given latitude can reduce a nation's ability to feed itself.

There are other ways in which human civilization has adapted to current regional conditions: Communities rely on air conditioning in the summer and/or heating in the winter to make regions tolerable. Harbors and coastal communities are built to suit current sea levels. In general, increased temperatures username_6 make warmer regions less tolerable and more expensive to live in ([through cooling and similar costs](https://www.nature.com/articles/s41467-019-10399-3)) and [more prone to deadly heat waves](https://www.yaleclimateconnections.org/2019/06/heat-waves-and-climate-change-is-there-a-connection/), while potentially making colder regions more tolerable and less expensive (through reduced heating costs). Similarly, dramatic cooling would also affect where everything grows, reduce growing degree days for growing plants, and making colder regions less tolerable and more costly.

While attempting to quantify the "[Country-level social cost of carbon](https://www.nature.com/articles/s41558-018-0282-y.epdf?author_access_token=XLBRLEGdT_Kv0n8_OnvpedRgN0jAjWel9jnR3ZoTv0Ms70oz073vBeHQkQJXsJbey6vjdAHHSPxkHEN8nflPeQI6U86-MxWO1T1uUiSvN2A-srp5G9s7YwGWt6-cuKn2e83mvZEpXG3r-J0nv0gYuA%3D%3D)," a 2018 study in *Nature Climate Change* by Kate Ricke, et. al. assessed the net economic impact on individual countries and concluded that the costs are "unevenly distributed": "Countries that incur large fractions of the global cost consistently include India, China, Saudi Arabia and the United States."

Northern countries such as Russia, Canada, Norway, Sweden, the United Kingdom, France, Germany, and Poland actually receive a slight direct benefit from climate change through factors such as reduced heating costs.


---

### Answer by username_8 on 2020-01-10. Score: -1

Much has been said about the negative effects, but there are positive effects as well. In UK thousands of old folk are speeded on their way to the promised land by hard winters, so milder winters username_6 save thousands of lives. Excessively hot summers can also cost lives, but in UK those killed by cold weather greatly outnumber those killed by heat waves. Another beneficial effect is that the NW and NE Passages username_6 be opened up to shipping, enabling ships to take short cuts to their destinations, use less fuel and thus cut CO2 emissions. Another benefit, provided the heating doesn't go too far, is that warm climates have greater biodiversity than cold climates. Of course, that means that cold-loving species like Gyrfalcons and Ptarmigan username_6 be pushed further north or onto higher ground (Gyrs have never bred in Britain,Ptarmigan do,and Snowy Owls occasionally). A number of new species including Little Egrets and Cattle Egrets are already colonising the south of UK.

A cooler climate would also have both positive and negative effects, but we are not likely to get that for some considerable time.

> **Comments:**
> **username_8**: I live in England , so I should know, and I've lived here for a very long while. It.s not the averages that kill people, but the below average temperatures. In Shropshire, 1982, the temperature was -26C.  
> **username_8**: Th4ere are more species in a square mile of tropical rainforest than on the entire Antarctic continent.  
> **username_10**: @ebv England doesn't have what other countries would recognise as cold winters, but it also has phenomenally poor housing stock. Without checking, I suspect username_8's probably right that cold kills more than heat at the moment. It'll change.  
> **username_5**: "warm climates have greater biodiversity than cold climates" is not strictly true. Biodiversity is highly dependent on water and nutrient availability. See figure 3 of https://www.researchgate.net/publication/215672861_Patterns_of_vascular_plant_diversity_at_continental_to_global_scale/figures for example. Deserts in the tropics have low biodiversity. Also, biodiversity username_6 not necessarily increase in temperate zones with warming - many locally adapted species username_6 die off, and only some species from warmer regions username_6 invade. Speciation is not likely to have major impacts in the short term.  
> **username_8**: I knew somebody would raise the objection that it isn't true of deserts, but I was stating a general principle. There are more species in one square mile of tropical rainforest than on the entire Antarctic continent. If there is one thing I know an enormous amount about it is the world's wildlife in general and UK wildlife in particular. You are only telling me what I already know.  

---

