# Isn't the planet cooling down? **URL:** \ **Category:** Factual Questions\ **Created:** [January 11, 2022, 8:47pm UTC](https://boards.straightdope.com/t/isnt-the-planet-cooling-down/957605 "2022-01-11T20:47:29Z")\ **Posts on this page:** 13\ **Page:** 2
**Author:** ![wolfpup](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/wolfpup/32/10618_2.png) [@wolfpup](https://boards.straightdope.com/u/wolfpup)\ **Post date:** [January 12, 2022, 1:31am UTC](https://boards.straightdope.com/t/isnt-the-planet-cooling-down/957605/21 "2022-01-12T01:31:36Z")
> [@engineer\_comp\_geek](#): > > > [@Chronos](#): > > > > Any temperature you could measure would be at the surface, which is definitely, unambiguously, hotter now than it was 500 years ago. > > Especially true given that 500 years ago the Earth was in the “little ice age” (roughly 1400s to the mid 1800s). Quite true, but that should not detract from the fact that the earth’s average global surface temperature is incontrovertibly warmer than at any time in the past 2000 years (and almost certainly very much longer, but paleoclimate data becomes less accurate the farther back you go). In particular, the average global temperature now is significantly warmer than in the so-called Medieval Warm Period, mainly because of the accumulation of post-industrial GHG emissions. ---
**Author:** ![md-2000](https://avatars.discourse-cdn.com/v4/letter/m/9d8465/32.png) [@md-2000](https://boards.straightdope.com/u/md-2000)\ **Post date:** [January 12, 2022, 5:53am UTC](https://boards.straightdope.com/t/isnt-the-planet-cooling-down/957605/22 "2022-01-12T05:53:23Z")
> [@wolfpup](#): > > In particular, the average global temperature now is significantly warmer than in the so-called Medieval Warm Period, mainly because of the accumulation of post-industrial GHG emissions. Is it? At that time, there was a climate that allowed (marginal) agricultural activity in southern Greenland coastal areas for a century or two, and from what I’ve seen on the news, we are only just now getting to that point again for Greenland. Or was the weather pattern different back then? ---
**Author:** ![md-2000](https://avatars.discourse-cdn.com/v4/letter/m/9d8465/32.png) [@md-2000](https://boards.straightdope.com/u/md-2000)\ **Post date:** [January 12, 2022, 6:35am UTC](https://boards.straightdope.com/t/isnt-the-planet-cooling-down/957605/23 "2022-01-12T06:35:44Z")
The heat emmission of the planet can be judged the same as for any warm object - how much heat is coming off? (Had this discussion over heat loss from the hot water tank. Go down to your hot water tank, put your hand on it - how warm to the touch is it?) in some places, heat is coming out of the earth as molten rock or old, faithful geysers. In other areas, permafrost exists, the ground is forever frozen (minus a bit of sun-induced global warming) and in “recent” times we’ve had whole sheets of ice covering fairly low latitudes. So heat conduction is obviously pretty minimal. The implication is that not much heat is escaping, but some is. ---
**Author:** ![wolfpup](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/wolfpup/32/10618_2.png) [@wolfpup](https://boards.straightdope.com/u/wolfpup)\ **Post date:** [January 12, 2022, 9:44am UTC](https://boards.straightdope.com/t/isnt-the-planet-cooling-down/957605/24 "2022-01-12T09:44:56Z")
> [@md-2000](#): > > > [@wolfpup](#): > > > > In particular, the average global temperature now is significantly warmer than in the so-called Medieval Warm Period, mainly because of the accumulation of post-industrial GHG emissions. > > Is it? At that time, there was a climate that allowed (marginal) agricultural activity in southern Greenland coastal areas for a century or two, and from what I’ve seen on the news, we are only just now getting to that point again for Greenland. Or was the weather pattern different back then? The evidence shows that the Medieval Warm Period was largely a regional phenomenon, not a global one, occurring in some parts of the Northern Hemisphere and notably absent in the Southern. Evidence for the unprecedented extent of truly global post-industrial warming was one of the major contributions to the paleoclimate chronology by Mann et al: [https://www.pnas.org/content/105/36/13252](https://www.pnas.org/content/105/36/13252) [https://www.pnas.org/content/pnas/105/36/13252/F3.large.jpg?width=800&height=600&carousel=1](https://www.pnas.org/content/pnas/105/36/13252/F3.large.jpg?width=800&height=600&carousel=1) ---
**Author:** ![echoreply](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/echoreply/32/3641_2.png) [@echoreply](https://boards.straightdope.com/u/echoreply)\ **Post date:** [January 12, 2022, 6:58pm UTC](https://boards.straightdope.com/t/isnt-the-planet-cooling-down/957605/25 "2022-01-12T18:58:58Z")
A [timely new article](https://link.springer.com/article/10.1007/s00376-022-1461-3) reports that the oceans contained a record high amount of heat in 2021. This is the sixth year in a row that the oceans have set a new record heat level. The scientific article says the oceans contain 14\pm11 zetajoules or 16\pm10 ZJ more energy than last year, depending on which dataset is used. The linked below popular press article says that’s the equivalent heat of 2.20752 \times 10^8 Little Boy atomic bombs. So yeah, getting warmer. > **[We study ocean temperatures. The earth’s seas just broke a heat increase...](https://www.theguardian.com/commentisfree/2022/jan/11/ocean-temperatures-earth-heat-increase-record)** > > Last year the oceans absorbed heat equivalent to seven Hiroshima atomic bombs detonating each second, 24 hours a day, 365 days a year ---
**Author:** ![am77494](https://avatars.discourse-cdn.com/v4/letter/a/d2c977/32.png) [@am77494](https://boards.straightdope.com/u/am77494)\ **Post date:** [January 12, 2022, 7:39pm UTC](https://boards.straightdope.com/t/isnt-the-planet-cooling-down/957605/26 "2022-01-12T19:39:16Z")
"_The total mass of Earth’s atmosphere is about 5.5 quadrillion tons, or roughly one millionth of Earth’s mass._ " - [How Much Does Earth’s Atmosphere Weigh? | Britannica](https://www.britannica.com/story/how-much-does-earths-atmosphere-weigh) Global Warming largely addresses only this one millionth of Earth’s mass. Even all water on earth combined is 0.05% of the Earth’s mass. [The Earth has lost a quarter of its water](https://sciencenordic.com/chemistry-climate-denmark/the-earth-has-lost-a-quarter-of-its-water/1462713#:~:text=Although%20water%20covers%2070%20percent,likelihood%20be%20a%20dead%20planet). ---
**Author:** ![echoreply](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/echoreply/32/3641_2.png) [@echoreply](https://boards.straightdope.com/u/echoreply)\ **Post date:** [January 12, 2022, 7:44pm UTC](https://boards.straightdope.com/t/isnt-the-planet-cooling-down/957605/27 "2022-01-12T19:44:52Z")
> [@am77494](#): > > " _The total mass of Earth’s atmosphere is about 5.5 quadrillion tons, or roughly one millionth of Earth’s mass._ " - [How Much Does Earth’s Atmosphere Weigh? | Britannica](https://www.britannica.com/story/how-much-does-earths-atmosphere-weigh) > > Global Warming largely addresses only this one millionth of Earth’s mass And because green house gases prevent heat from the atmosphere from radiating back into space, the heat is primarily being absorbed by the oceans. The article below says that 90% of the trapped heat due to anthropogenic climate change is in the oceans. > **[Climate Change: Ocean Heat Content](https://www.climate.gov/news-features/understanding-climate/climate-change-ocean-heat-content)** > > More than 90 percent of the warming that has happened on Earth over the past 50 years has occurred in the ocean. Not all of that heating is detectable yet at the surface ---
**Author:** ![DesertDog](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/desertdog/32/11503_2.png) [@DesertDog](https://boards.straightdope.com/u/DesertDog)\ **Post date:** [January 12, 2022, 8:10pm UTC](https://boards.straightdope.com/t/isnt-the-planet-cooling-down/957605/28 "2022-01-12T20:10:15Z")
> [@md-2000](#): > > in “recent” times we’ve had whole sheets of ice covering fairly low latitudes. Although not totally accepted, signs point to two periods where _everything_ was ice-covered ([snowball Earth](https://en.wikipedia.org/wiki/Snowball_Earth)), 2100 and 650 Mya when presumably the radiogenic heat mentioned in **MrDibble** ’s link would be greater than the more recent glaciation periods ---
**Author:** ![engineer\_comp\_geek](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/engineer_comp_geek/32/504_2.png) [@engineer\_comp\_geek](https://boards.straightdope.com/u/engineer_comp_geek)\ **Post date:** [January 13, 2022, 1:00am UTC](https://boards.straightdope.com/t/isnt-the-planet-cooling-down/957605/29 "2022-01-13T01:00:20Z")
**Moderator Note** Let’s all keep in mind that this is not a general discussion of climate change. Some discussion is relevant, as the OP did ask later in the thread about measuring the Earth’s temperature from several hundred million miles away, which would end up measuring the Earth’s surface temperature. However, the OP is about the overall temperature of the Earth, not the temperature of the Earth’s surface or atmosphere. Let’s not get sidetracked into a general discussion of climate change as that is a topic for a different thread. ---
**Author:** ![engineer\_comp\_geek](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/engineer_comp_geek/32/504_2.png) [@engineer\_comp\_geek](https://boards.straightdope.com/u/engineer_comp_geek)\ **Post date:** [January 16, 2022, 2:04pm UTC](https://boards.straightdope.com/t/isnt-the-planet-cooling-down/957605/30 "2022-01-16T14:04:53Z")
In my news today, a mew study indicates that the Earth’s interior may be cooling faster than expected. New laboratory measurements of the type of material found at the boundary between the core and the mantle found that this material has a higher thermal conductivity than previously thought. This is significant because there is a rather substantial heat differential between the core and mantle, so this boundary layer could be conducting heat out of the core at a much higher rate than previously predicted. > **[Earth’s Interior Is Cooling “Much Faster Than Expected”](https://scitechdaily.com/earths-interior-is-cooling-much-faster-than-expected/)** > > Researchers at ETH Zurich have demonstrated in the lab how well a mineral common at the boundary between the Earth’s core and mantle conducts heat. This leads them to suspect that the Earth’s heat may dissipate sooner than previously thought. The... ---
**Author:** ![CC](https://avatars.discourse-cdn.com/v4/letter/c/f1d935/32.png) [@CC](https://boards.straightdope.com/u/CC)\ **Post date:** [January 16, 2022, 3:14pm UTC](https://boards.straightdope.com/t/isnt-the-planet-cooling-down/957605/31 "2022-01-16T15:14:37Z")
Excellent. Thank you. This actually does answer my question. Yes, the earth is cooling down. (And thanks for reorienting the nature of the posts.) ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [January 17, 2022, 3:02am UTC](https://boards.straightdope.com/t/isnt-the-planet-cooling-down/957605/32 "2022-01-17T03:02:45Z")
Most of the mass or volume of the Earth is cooling, with only a small portion at the surface heating up. But the part that’s heating up is heating up much quicker than the part that’s cooling down. ---
**Author:** ![Riemann](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/riemann/32/3133_2.png) [@Riemann](https://boards.straightdope.com/u/Riemann)\ **Post date:** [January 17, 2022, 3:58am UTC](https://boards.straightdope.com/t/isnt-the-planet-cooling-down/957605/33 "2022-01-17T03:58:08Z")
> [@Chronos](#): > > part that’s heating up is heating up much quicker than the part that’s cooling down By 5 orders of magnitude. The mantle is cooling at a rate of about 1 deg in 5 million years. [https://www.sciencenews.org/article/earth-mantle-cooling-faster-expected](https://www.sciencenews.org/article/earth-mantle-cooling-faster-expected) The surface has warmed about 1 deg in the last 50 years. [Climate Change: Global Temperature | NOAA Climate.gov](https://www.climate.gov/news-features/understanding-climate/climate-change-global-temperature) > [@CC](#): > > Yes, the earth is cooling down. So absent careful explanation of what you’re talking about, I would say this assertion is somewhere between “wrong” and “highly misleading”. [Previous page](https://boards.straightdope.com/t/isnt-the-planet-cooling-down/957605.md?page=1)