Climate Change & Anthropocene Extinction 33: ‘Temperate biodiversity’ faces specific challenges

The response of endemic biodiversity to climate change in Earth’s temperate climate zones is complex. A new study suggests that species that have evolved in regions with relatively high natural climate variability may at the same time be more resilient and more vulnerable to the effects of steadily rising temperatures:

Genetic diversity of species from temperate climate zones, stemming from the large seasonal and multi-annual climate fluctuations of these regions, may place them at an adaptive advantage in face of 21st-century climate change. This same natural climate variation may however also blind these temperate-zone species to the underlying climate trend, misguiding them to disperse or even evolve in false directions, decreasing their chance of survival.

Temperate biodiversity complex response to climate change
Continue reading

Climate Change & Anthropocene Extinction 32: COP23 emission targets still lead beyond +3 degrees

Climate change is just one driver of the Holocene-Anthropocene Mass Extinction. But it will be a powerful one, as global emission reduction commitments – that will be discussed in the following two weeks in the German city of Bonn during the ‘COP23′ UN climate conference – still lead to a three degrees warmer world, or worse, as this updated UNEP graph illustrates:

Emission targets 2030 lead beyond 3 degrees warming - COP23 Bonn
Continue reading

Climate Change & Anthropocene Extinction 31: ‘New’ great ape species – directly at risk of extinction

Say hello to Pongo tapanuliensis, or ‘the Tapanuli orangutan’ – a close relative of yourself who had been hiding in plane sight on the Indonesian island of Sumatra.

Sadly, unless hunting and deforestation are halted, you can also immediately say goodbye – as just 800 individuals remain of this newly discovered ape species, living scattered across a fragmented rainforest of about 1,000 square kilometres.

Pongo tapanuliensis orangutan species
Continue reading

Climate Change & Anthropocene Extinction 30: Heavy breathing tropical forests under record heat

Today the WMO announced that the atmospheric CO2 concentration last year rose at a record high speed: +3.3 ppm – jumping from 400.0 ppm in 2015 to 403.3 in 2016. The annual average rise is close to 2 ppm.

A few days earlier NASA scientists had explained why the global CO2 rise has suddenly rapidly accelerated: rainforests across Earth’s tropics, suffering unprecedented heat and drought, and exhaling a massive amount of CO2 (9.2 billion tonnes) – adding over 50 percent to the global fossil fuelled economy:

tropical forests CO2 source climate change
Continue reading

Climate Change & Anthropocene Extinction 29: Last straw Madagascar bamboo lemur drying out

When you’re looking at the effects of climate change on the forests of Africa, you may be inclined to overlook Madagascar, the continent’s largest island. But especially when biodiversity is your concern, it deserves special attention.

In fact Madagascar has more endemic-only tree species than any other African country. And although the Congo Basin – Africa’s tropical rainforest heartland – is rich in iconic primates like the chimpanzee, bonobo and gorilla, Madagascar is the single home of a uniquely separate clade of primates called ‘lemurs’, which evolved independently from monkeys and apes.

Madagascar bamboo lemur threatened climate change
Continue reading

Climate Change & Anthropocene Extinction 28: If the Amazon goes, so may Africa’s rainforests

The Congolese rainforests are the world’s second largest remaining tropical rainforest expanse and a 60 gigatonne carbon store. Although climate models have a hard time predicting rainfall changes over the Congo Basin and despite a multi-decade drying trend, these forests in the heartland of tropical Africa are generally thought to be relatively resilient to the effects of climate change – at least when compared to the Amazon, a well-researched climate tipping point.

But ironically the possible large-scale drying and disappearance of the Amazon rainforest might also be the climatic Achilles’ heel of the Congolese rainforests.

Drying rainforests of Amazon and Congo due to global climate change, according to NOAA NCEP
Continue reading

Climate Change & Anthropocene Extinction 27: Africa is warming fast, but what about Congo Basin?

21st century climate change affects the entire globe: every ecosystem, every mountain range, all the glaciers, all the land, the oceans. But of all continents it’s often said that Africa will face the biggest impacts.

African climate change is far from a uniform process though. Large geographical differences occur across the continent, that together form a pattern, as for all the African regions changes in temperature and precipitation are directly influenced by changes in the general circulation of the atmosphere.

While it’s clear that some regions will get really dry, others may get really wet, and some may warm faster than others; it is climate impacts on Africa’s tropical heartland that are perhaps most uncertain, as different climate models have a hard time capturing both the present and future convective precipitation that the Congolese rainforests depend on – rainforests that in turn are hugely important for the health of our planet as they are Africa’s densest biodiversity hotspot and a carbon store weighing in at a 60 gigatonne significance to the global climate system.

African forest elephants & Congolese climate change
Continue reading

Climate Change & Anthropocene Extinction 26: Congolese rainforests store twice as much carbon

A new study, published earlier this year in Nature, shows that the Congolese rainforests store far more carbon than previously thought: over 60 billion tonnes, about half of which in the living biomass of the forest trees, and the other half as shallow peat – mainly in the ‘Cuvette Central’, a huge forested wetland in its centre:

Congo rainforest carbon store twice as large, Nature study shows

If this terrestrial carbon store were cut down, burned, drained, or otherwise oxidised (for instance through increasing droughts in the Congo Basin) that would equate to emissions of approximately 220 billion tonnes of CO2. And that makes protection of Africa’s densest biodiversity hotspot of immediate significance for the stability of the global climate system.

Continue reading

Climate Change & Anthropocene Extinction 25: Congo rainforest shows drying trend – and degradation

The climate over the Congolese rainforests (in the central tropics of Africa) seems to show a drying trend over the last four decades. And although this deviation is smaller than multi-annual variation, the average decline in precipitation does lead to forest degradation in the world’s second-largest remaining tropical rainforest.

Climate change over Congo rainforests: declining precipitation trend
Continue reading

Climate Change & Anthropocene Extinction 24: Insects Germany declined 76% in just 27 years(!)

The numbers of flying insects in nature reserves throughout Germany show a staggering decline. Taken on average over the months of April to October between 1989 and 2016 insect numbers declined 76%. In mid-summer measurements show an even more rapid decline, with insect numbers now 82% down compared to just 27 years ago.

This we learn from a study by a group of German and Dutch ecologists of Radboud University and the Entomological Society Krefeld that was published yesterday.

Anthropocene Extinction graph: insect decline Germany
Continue reading