7000-Year-Old Trees Uncovered High Up In The Rockies

From NOT A LOT OF PEOPLE KNOW THAT

By Paul Homewood

A melting patch of ice in the Rockies is uncovering trees that were growing 7000 years ago:

Significance

Recent warming has decreased snow and ice cover and increased the elevation of most subalpine treelines around the world. A mid-Holocene (c. 5,950 to 5,440 cal y BP) whitebark pine forest preserved within a perennial ice patch in the Greater Yellowstone Ecosystem provides insights into the consequences of past climate change and ecosystem dynamics. Mid-Holocene treeline expanded ~180 m above its modern elevation when warm-season temperatures were similar to mid-to-late-20th-century conditions. Treeline elevation was subsequently lowered due to periods of cooling related to increased volcanism, but primarily from declining summer insolation during the late Holocene. As current ice-patch temperatures exceed the warmest mid-Holocene conditions, we expect regional loss of ice patches and possibly renewed upslope treeline expansion.

Abstract

Climate-driven changes in high-elevation forest distribution and reductions in snow and ice cover have major implications for ecosystems and global water security. In the Greater Yellowstone Ecosystem of the Rocky Mountains (United States), recent melting of a high-elevation (3,091 m asl) ice patch exposed a mature stand of whitebark pine (Pinus albicaulis) trees, located ~180 m in elevation above modern treeline, that date to the mid-Holocene (c. 5,950 to 5,440 cal y BP). Here, we used this subfossil wood record to develop tree-ring-based temperature estimates for the upper-elevation climate conditions that resulted in ancient forest establishment and growth and the subsequent regional ice-patch growth and downslope shift of treeline. Results suggest that mid-Holocene forest establishment and growth occurred under warm-season (May-Oct) mean temperatures of 6.2 °C (±0.2 °C), until a multicentury cooling anomaly suppressed temperatures below 5.8 °C, resulting in stand mortality by c. 5,440 y BP. Transient climate model simulations indicate that regional cooling was driven by changes in summer insolation and Northern Hemisphere volcanism. The initial cooling event was followed centuries later (c. 5,100 y BP) by sustained Icelandic volcanic eruptions that forced a centennial-scale 1.0 °C summer cooling anomaly and led to rapid ice-patch growth and preservation of the trees. With recent warming (c. 2000–2020 CE), warm-season temperatures now equal and will soon exceed those of the mid-Holocene period of high treeline. It is likely that perennial ice cover will again disappear from the region, and treeline may expand upslope so long as plant-available moisture and disturbance are not limiting.

https://www.pnas.org/doi/10.1073/pnas.2412162121

The paper incorrectly claims that recent warming is a new phenomenon, but provides no data to back this up.

However many tree line studies have conclusively shown that tree lines in the Rockies were much higher than now as recently as the Middle Ages.

HH Lamb : Climate, History and the Modern World


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January 15, 2025 at 12:02PM

Being called “Far Right” is like being called a witch in the middle ages

By Jo Nova

A “Far Left Politician” is practically invisible, and usually harmless. But a Far Right politician is dangerous.

(To the people who use namecalling to silence opponents).

💯 pic.twitter.com/0kSpy65HjK

— Rothmus 🏴 (@Rothmus) January 8, 2025

To be called “Far Right” implies someone is a horrible person, and you should probably hiss at them if they get too close. But on the prime time news, even bureaucrats pushing for One World Government, or slave owning dictators like President Xi are rarely introduced as “the Far Left President Xi”. That would give the game away, wouldn’t it? There would be constant reminders of the dangers of going “too far left”.

In its purest form the political right just want individual rights and smaller government, yet the “definition” of far right keeps shape-shifting to become somehow horribly authoritarian, “like Hitler”, of course, (the Socialist). Who benefits from this absurd definition? — Big Leftist collectivists, of course.

We the people cannot even have a conversation with easily recognizable words. The word fog is not an accident.

The real horrors are not the right wing people waving a national flag, and talking about individual rights, but the far left […]

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January 15, 2025 at 11:56AM

Hype Uncovered: ‘Nature’ Study Shows That Permafrost Is Not A Climate Tipping Point

Germany’s Klimanachrichten here presents peer-reviewed climate science that shows permafrost is not really a tipping point we need to worry about. 

Here’s the text of what is reported on the video: 

“Permafrost soils store a lot of CO2 and are often described as a critical tipping element in the Earth system, which suddenly and globally collapses above a certain level of global warming. Yet, the view of a ticking time bomb that initially behaves rather calmly and only ignites at a certain warming threshold is controversial among researchers. According to scientific data, this claim is not correct, as an international study team led by the Alfred Wegener Institute has now been able to show.

According to the study, there is not one specific global climate tipping point, but many local and regional tipping elements that “ignite” at different times, accumulate over time and cause the permafrost to thaw in step with climate change.

Permafrost soils cover around a quarter of the land area in the northern hemisphere and store vast amounts of organic carbon in the form of dead plant remains. These are not decomposed when frozen. Only when the permafrost thaws do microorganisms become active and release a lot of carbon into the atmosphere as CO2 and methane. Rising global temperatures could therefore activate these gigantic reservoirs and massively increase climate change through additional emissions. In the public debate, there is therefore repeated talk of a “ticking carbon time bomb”. This is based on the assumption that permafrost, like the Greenland ice sheet, is one of several tipping elements in the Earth system. According to this, the permafrost initially disappears only slowly in the course of global warming. Only when a critical threshold value is exceeded do the thawing processes suddenly intensify themselves and a rapid, irreversible global permafrost collapse sets in. Although such a thawing scenario is often suspected, it has not yet been possible to clarify whether such a threshold value really exists and at what temperature it could be exceeded.

An international research team led by Jan Nitzbon from the Alfred Wegener Institute, Helmholtz Center for Polar and Marine Research (AWI) has now gotten to the bottom of this question. The AWI researcher explains, quote: “In fact, the depiction of permafrost as a global tipping element is controversial in research. The Intergovernmental Panel on Climate Change (IPCC) also points out this ambiguity in its latest assessment report. We wanted to close this knowledge gap. For our study, we compiled the available scientific literature on the processes that can influence and accelerate the thawing of permafrost. Underpinned by our own data analysis, we evaluated all current findings on thawing processes to determine whether and on what spatial scale – local, regional, global – they can lead to self-sustaining thawing and thus to a ‘tipping point’ at a certain warming threshold.” End quote.

The results of the study clearly show that there are self-reinforcing, partly irreversible geological, hydrological and physical processes, but these only have a local or regional effect. One example is the formation of so-called thermokarst lakes. This involves ice melting in permafrost soils, which then sink. The meltwater collects on the surface and forms a dark lake that absorbs a lot of solar energy. This further increases the warming of the permafrost beneath the lake and creates a self-perpetuating dew process in the area around the lake. Similar amplifying feedbacks were also found in other processes relevant to permafrost, such as the loss of boreal coniferous forests due to fires – but here too only on a local to regional scale. There is no evidence for self-reinforcing internal processes that would simultaneously affect the entire permafrost above a certain degree of global warming and accelerate thawing globally. Even the estimated release of greenhouse gases would not lead to a global leap in global warming at least until the end of the century. The depiction of permafrost as a global tipping element is therefore misleading.

The study was published in Nature Climate Change in June 2024.”

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January 15, 2025 at 11:51AM

Climate False Alarms about Agriculture

 

 

 

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January 15, 2025 at 11:16AM