Low fish catch – India
Maharashtra witnessed lowest fish catch in 45 years in 2019. Fishers have also reported a 50% decline in their annual fish catch, attributing recurring cyclones for reducing their fishing window. Fish migrate from warm waters to cool waters, a phenomenon that has already begun as the Indian ocean is warming up is one of the reasons for lower fish catch. The marine algae that is the base of aquatic food web has been disappearing in the western Indian Ocean owing to rising sea temperatures.
‘Landmark’ Irish climate case sets global precedent
The Supreme Court ruling that will force the Government to review its climate action plan will have significant international repercussions, according to an expert from the United Nations.
For the first time in Ireland, and only the second time in the world, the highest national court has required a government to revise its national climate policy.
The case dubbed “Climate Case Ireland,” lodged by Friends of the Irish Environment (FIE) against the Government, argued that the State’s National Mitigation Plan does not do enough to tackle climate change.
Yesterday’s ruling rejected the plan as invalid and in breach of the Climate Action and Low Carbon Development Act 2015, overturning a High Court ruling last year which said that it could not second guess government policy.
Increasing Arctic freshwater is driven by climate change
New, first-of-its-kind research from CU Boulder shows that climate change is driving increasing amounts of freshwater in the Arctic Ocean. Within the next few decades, this will lead to increased freshwater moving into the North Atlantic Ocean, which could disrupt ocean currents and affect temperatures in northern Europe.
Since the 1990s, the Arctic Ocean has seen a 10% increase in its freshwater. That’s 2,400 cubic miles (10,000 cubic kilometers), the same amount it would take to cover the entire U.S. with 3 feet of water.
The salinity in the ocean isn’t the same everywhere, and the Arctic Ocean’s surface waters are already some of the freshest in the world due to large amounts of river runoff.
This freshwater is what makes sea ice possible: it keeps cold water at the surface, instead of allowing this denser liquid to sink below less dense, warm water. In this way, the Arctic Ocean is much different than other oceans. But as more freshwater exits the Arctic, this same stabilizing mechanism could disrupt the ocean currents in the North Atlantic that moderate winter temperatures in Europe.
Such disruptions have happened before, during the “great salinity anomalies” of the 1970s and 80s. But these were temporary events. If too much cold freshwater from the Arctic continuously flows into the North Atlantic, the ocean turnover could be disrupted more permanently.
Forests Migrate — But Not Fast Enough For Climate Change
We’re all familiar with migration: Wildebeests gallop across Africa, Monarch butterflies flit across the Americas … but forests migrate, too, an agonizingly slow migration, as forests creep inch by inch to more hospitable places.
Individual trees are rooted in one spot. As old trees die and new ones sprouts up, the forest is — ever so slightly — moving. A forest sends seeds just beyond its footprint in every direction, but the seeds that go to the north — assuming the north is the more hospitable direction — thrive a little more than the ones that fall to the south. Over time, this forest would march steadily northwards.
Rivers and climate change in Europe
Studying historical documents from 5 centuries, scientists from Vienna University were able to compare flood events from the past with recent flood events in Europe. This combination of historical and hydrological research provides evidence for the strong influence of climate change on rivers and floodings. Floods tend to be larger, the timing has shifted and the relationship between flood occurrence and air temperatures has reversed.
Global warming shrinks bird breeding windows
For breeding birds, timing is everything. Most species have just a narrow window to get the food they need to feed their brood—after spring’s bounty has sprung, but before other bird species swoop in to compete. Now, a new study suggests that as the climate warms, birds are not only breeding earlier, but their breeding windows are also shrinking—some by as many as 4 to 5 days. This could lead to increased competition for food that might threaten many bird populations.
Birds typically time their breeding to cues signaling the start of spring, so that their chicks hatch when food like plants and insects is most abundant. But global warming has pushed many species to breed earlier in the year; that effect is especially prominent at higher latitudes, where temperatures are rising faster than near the equator. Few studies, however, have examined how climate change affects the duration of breeding windows, which closely track the number of chicks born each year as well as overall population trends.
To find out how the length of breeding periods has changed over time, a team examined a data set spaning from 1975 to 2017 which includes the nesting records of 73 species and more than 820,000 birds from a 1000-square-kilometer area in Finland’s boreal forests. Each year, trained volunteers placed uniquely numbered rings around the legs of newly hatched chicks to track their movements and survival. Because chicks had to be a certain size to get a ring, the researchers were able to use the timing of the tagging to work out when each chick had hatched—and therefore when breeding had occurred.
On average, the beginnings and ends of the breeding periods are occurring earlier in the year. However, the ends are shifting back faster than the beginnings, resulting in an average breeding window that is 1.7 days shorter in 2017 than it was in 1975. During that same period, Finland’s average temperature rose by 0.8oC, suggesting many bird species are actively responding to changing temperatures.
Scientists predict that Earth’s atmosphere will soon contain the same high level of carbon dioxide that existed at the peak of the Pliocene Epoch warmth 3 million years ago, when temperatures were 5 to 7 degrees Fahrenheit warmer and sea levels were 65 feet higher.
A report published in the journal Nature Scientific Reports says that given the level of emissions present at the start of the study, prior to the coronovirus lockdowns, CO2 levels could surpass 427 parts per million within five years. The authors say that the comparison with the Pliocene shows what is likely to happen in the future as the Earth responds to the buildup of greenhouse gas emissions.
No quick fix in fight against global warming
Slashing greenhouse gas emissions would probably not yield visible results until mid-century, researchers have said, cautioning that humanity must manage its expectations in the fight against global warming.
Even under optimistic scenarios in which carbon pollution falls sharply, climate change will continue for decades, they reported on Tuesday in the journal Nature Communications.
Two factors will make it difficult to feel and measure a drop in Earth’s surface temperature, if and when that happens.
One is lag time – Over the past half-century, human activity has loaded the atmosphere with more than 1-trillion tonnes of planet-warming carbon dioxide (CO2), a gas that lingers for hundreds of years.
The second factor is natural variability – Over the past half-century the planet has warmed 0.2°C every decade, mainly due to the burning of fossil fuels.
Thin Arctic Ice
The biggest ever science expedition to the Arctic encountered extremely thin sea ice, which could threaten future efforts to study the region.
A team on board the Polarstern icebreaker ship began drifting last September until their vessel became locked in an ice floe. In the area off the Russian continental shelf where they started their journey, the ice was exceptionally thin compared with what models had predicted for the past two decades. The ice was around 50 centimetres thick, while it had been around 150 to 160 centimetres thick the previous three years.
Italian glacier turns pink due to global warming-linked algae
In a first for Italy, pink snow is observed on parts of the Presena glacier, in the north of the country. The phenomenon is caused by algae that develops when snow melts, simultaneously colouring the ice a darker colour. In a vicious circle, the algae in turn increases the rate at which the snow melts by accelerating the absorption of radiation.
Warming Waters Inhibit Fish from Reproducing
As many as 60 percent of the world’s fish species could struggle to breed and reproduce if climate change causes the Earth to warm by 5 degrees Celsius over the next 80 years, the current projection for what will happen if greenhouse gas emissions continue unchecked, according to a new study.
A study released Thursday in the journal Science that examined nearly 700 species of freshwater and saltwater fish found that 6 in 10 species would be affected if bodies of water around the world continue to warm. If global warming was limited to 1.5 degrees Celsius, the study’s authors added, that number falls as low as 1 in 10 species.
Species unable to reproduce in traditional habitats may either move to deeper water or further north and would result in local extinctions.
Global Warming Has Undone 6,500 Years Of Worldwide Cooling
Caused primarily by the burning of fossil fuels global warming circulates carbon dioxide (CO2), methane and other greenhouse gases into the atmosphere and is leading to the gradual heating of Earth’s surface, oceans and atmosphere.
A new study has surfaced suggesting that global warming has toppled six millennia of global cooling in the last 150 years.
The findings of the study show that global cooling started approximately 6,500 years ago when the long-term average global temperature peaked at around 0.7 degree Celsius warmer than the mid-nineteenth century. Since then, accelerating greenhouse gases have contributed to global average temperatures that are now moving past one degree Celsius above the mid-19th century.
South Pole Warming Faster
The South Pole has warmed three times faster than the rest of the planet in the last 30 years due to warmer tropical ocean temperatures, new research showed Monday. Antarctica’s temperature varies widely according to season and region, and for years it had been thought that the South Pole had stayed cool even as the continent heated up.
Researchers in New Zealand, Britain and the United States analysed 60 years of weather station data and used computer modelling to show what was causing the accelerated warming. They found that warmer ocean temperatures in the western Pacific had over the decades lowered atmospheric pressure over the Weddell Sea in the southern Atlantic. This in turn had increased the flow of warm air directly over the South Pole — warming it by more than 1.83°C since 1989.
Authors of the research said the natural warming trend was likely boosted by manmade greenhouse gas emissions and could be masking the heating effect of carbon pollution over the South Pole.
Beavers Gnaw at Permafrost
The beaver may be an unlikely agent of climate change, but the cuddly-looking creatures are transforming the Arctic landscape in a way that could be exacerbating global warming, a new study has suggested.
With their sharp teeth, beavers fell trees and shrubs and build dams, which flood small valleys and form new lakes that can cover several hectares of land. These new water bodies contribute to the thawing of the frozen permafrost soil, which is a huge natural reservoir of methane — a potent greenhouse gas. Scientists are concerned that as the permafrost degrades, the climate-changing methane and carbon leak into the atmosphere.
Six Month Deadline
The Paris-based International Energy Agency has warned that world leaders have only six months to take measures to control carbon emissions, before a post-lockdown recovery brings a surge in the greenhouse gases that may be impossible to curb. The organization cautions that without immediate action, reaching the targets to address global warming will not be possible.
“This year is the last time we have, if we are not to see a carbon rebound,” said Fatih Birol, executive director of the International Energy Agency. He told The Guardian governments must design economic recovery packages that promote shifts away from carbon-based fuels.
Antarctic Penguin Boom
Antarctic penguins could experience a ‘population boom’ due to global warming as melting sea ice means they have to spend less time foraging for food. Japanese scientists describe the Adélie species of penguin, which is native to Antarctica, as a ‘rare global warming winner’ thanks to melting ice.
In low-ice conditions, penguins are able travel more by swimming than by walking, which increases their access to foods such as fish and krill. For Adélies, swimming is four times faster than walking, meaning faster access to food and, in turn, healthier offspring and longer lifespans.