Category: Climate Change Impacts

Rain and heat extremes set to grow

Rain and heat extremes set to grow

By Tim Radford

Millions of people in Asia and Europe can expect fiercer heat extremes, even if the world makes promised emissions cuts. The big heat is on the way: over 50% of Europe, and across more than a quarter of east Asia, the probability of record-breaking heat extremes will increase fivefold.

Over more than 35% of North America, Europe and East Asia, the chance of record-breaking rainfall will increase by more than threefold.

And this will happen even if the world’s nations honour the commitments they have already made to contain global warming by switching from fossil fuels to renewable energy sources.

That would result in an average rise in global temperatures of between 2°C and 3°C by 2100. If the 195 nations that signed a climate accord in Paris in 2015 actually honour their collective vow to contain planetary average warming to about 1.5°C above historic averages, there will still be record-breaking temperatures and more intense extremes of wet and dry – but over a smaller proportion of the globe, according to a new study.

“We can use this kind of research to make decisions that both build resilience now and help us be prepared for the climate that we will face in the future”

That is, a difference of even 1°C in outcome means a huge difference in impact across the planet. The study confirms once again, with a different methodology, that action planned now to meet the Paris targets is not enough: nations must do more.

Noah Diffenbaugh of Stanford University in California and colleagues report in the journal Science Advances that they took a statistical framework already tested on drought in California and floods in northern India and applied it to the entire planet to see what difference global action might make.

The point of such research is to prepare national and civic authorities for extremes to come, and Professor Diffenbaugh and his fellow researchers have already used their statistical approach to connect human-induced global warming with drought in California, and changes in monsoon rainfall in Asia.

Conflict link

They have also applied mathematical techniques to connect climate change to the greater likelihood of conflict and violence.

The scientists warn that their methodology is conservative, and based not just on sophisticated computer simulations of climate, but also direct observations of climate extremes of temperature, drought and flood.

“Damages from extreme weather and climate events have been increasing, and 2017 was the costliest year on record. These rising costs are one of many signs that we are not prepared for today’s climate, let alone for another degree of global warming,” said Professor Diffenbaugh.

“But the good news is we don’t have to wait to play catch-up. Instead we can use this kind of research to make decisions that both build resilience now and help us be prepared for the climate that we will face in the future.”

This article was originally published on Climate News Network and is shared under a Creative Commons license

Cover photo by Alex Block on Unsplash.
Worryingly high temperatures in the Arctic while Europe shivers in the cold

Worryingly high temperatures in the Arctic while Europe shivers in the cold

By Elisa Jiménez Alonso

February should be one of the coldest months in the Arctic, however, it seems the North Pole is running a fever this year. With average temperatures up to 20 degrees Celsius above normal, the current weather is being described as an extreme event by experts.

Zack Labe, a PhD candidate at the University of California, has been sharing data from his research online and it shows worrying signs and trends. While Arctic temperatures have reached record highs for this time of year, Arctic sea ice has reached record lows.

While warm weather intrusions have happened in the past, they used to be a rarity. Speaking to the Washington Post, Robert Graham from the Norwegian Polar Institute said “It happened in four years between 1980-2010, but has now occurred in four out of the last five winters.” A study released last July confirms that since 1980 these warming events have become more frequent and last longer than they used to.

The warm temperatures are intrinsically linked to the rapid loss of sea ice. In mid-February this year, global sea ice extent fell to its lowest level ever measured. This decline has long been described as one the Earth’s most important tipping points: As the reflective white ice melts due to rising temperatures, it exposes the darker ocean surface which more easily absorbs heat warming up ocean waters and melting even more ice.

As a result of retreating sea ice, Cape Morris Jesup, at the very northern tip of Greenland, has had over 60 hours of above freezing temperatures since the beginning of 2018.

Meanwhile, Europe is experiencing particularly cold weather. This, odd as it may sound, is also linked to the warm Arctic temperatures. As pressure builds up over Scandinavia, winds that flow clockwise around such high-pressure systems drag cold Siberian air over Europe. Northern and Eastern Europe are set to feel the brunt of this cold spell, with conditions lasting 10 days or longer.

Cover photo by NASA Goddard Space Flight Center (CC BY 2.0).
Climate adaptation vital to limit damage so far

Climate adaptation vital to limit damage so far

By Tim Radford

The risk of flooding to millions more people in Asia, Europe and North America will rise, demanding climate adaptation for a warmer world. The probable changes as the world heats are so great that climate adaptation to cope with the inevitable is now essential, scientists are warning.

Forest damage, drought and floods, for example, will all worsen, and tidal ranges are already changing. More than half of all the natural vegetation of California is at risk as temperatures rise.

Even were the US and other nations to honour the promises made in the Paris Agreement of 2015, one fourth of California’s natural wilderness would be under stress from global warming, a new study shows.

And on top of temperature rise, California is increasingly at risk from severe drought, says a different study. US government scientists believe they have established a link between the retreat of Arctic sea ice and a decline in rainfall in the Golden State.

Drought and flood

And while California becomes ever more parched, its forests at ever-greater risk of insect attack and wildfire, 43 other US states face a dramatic increase in flood hazard, with a tenfold rise in the numbers of people at risk from the worst river floods.

And – although President Trump has dismissed climate change as a hoax and announced a withdrawal from the Paris Agreement to limit the use of fossil fuels – the tide gauges of the Chesapeake and Delaware Bays on the east coast of the US tell a different story. They confirm that climate change has already begun to affect high and low water tides.

US researchers report in the journal Ecosphere that they looked at the consequences for California if global greenhouse gas emissions continue at their present rate, to go on fuelling global warming.

They mapped 30 different vegetation types – California’s canopy includes a huge variety of mountain conifer, forest coastal woodland, upland sagebrush scrub, grassland and so on – and considered nine climate and precipitation variables, and then looked at computer models of future global warming, which predict – at worst – a global average rise of 4.5°C by 2100.

“Mitigating future climate change must be accompanied by adapting to the climate change we have already caused. Doing nothing will be dangerous”

“At current rates of emissions, about 45-56°C of all the natural vegetation in the state is at risk, or from 61,190 to 75,866 square miles,” said James Thorne of the University of California Davis, who led the study.

“If we reduce the rate to Paris Accord targets, those numbers are lowered to between 21 and 28% of the lands at climatic risk.” The research measures only the impact of climate change: not of the accompanying hazards.

During the 2012-2016 Californian drought – the worst on record – more than 127 million trees died of insect infestation, and wildfire devastated huge tracts of forest and scrub.

And according to researchers at Lawrence Livermore National Laboratory, more drought could be on the way. They report in Nature Communications that the steady attrition of sea ice in the Arctic Ocean triggers a change in atmospheric convection over the tropical Pacific, which creates the right conditions for an atmospheric ridge over the North Pacific, which means California gets a lot sunnier, and therefore drier.

Rising rivers

“On average, considering a 20-year mean, we find a 10-15% decrease in California’s rainfall. However some individual years could become much drier, and others wetter,” said Ivana Cvijanovic, who led the research. “The recent California drought appears to be a good illustration of what sea ice-driven precipitation decline should look like.”

Elsewhere in the US, drought may not be the big problem. German researchers report in the journal Science Advances that they calculated the necessary increase in flood protection over the next 25 years worldwide, as the planet warms.

They looked not just at individual countries but at cities too, to calculate the numbers at hazard of rising rivers, including Europe.

In Germany, the numbers at risk from the worst 10% of all floods will rise sevenfold. In North America, the increase will be tenfold. In the US, 43 states could see more damage from the worst floods.

Asia’s risk greatest

The overall numbers at risk are greatest in Asia – 70 million people now, and 156 million by 2040. The scientists make the case that governments need to think about adaptation. The surprise was that even the most developed nations would be affected.

“The findings should be a warning to decision-makers,” said Anders Levermann, of the Potsdam Institute for Climate Impact Research, and one of the authors. “If they choose to ignore the issue, sadly enough disaster will come.

“The time has come where mitigating future climate change must be accompanied by adapting to the climate change we have already caused. Doing nothing will be dangerous.”

And the impact of climate change so far is now backed up by evidence in the Journal of Geophysical Research. Once again, the research is driven by a concern to identify future sources of flooding or erosion.

Shifting tides

Oceanographers built a computer model based on a century of measurements of the tides at 15 locations in the Chesapeake and Delaware Bays on the US eastern coast. Overall, by 2100, sea levels could rise by as much as a metre.

They found evidence that sea level rise so far has already begun to change the ranges of low and high tides – in some cases by up to 20% – which in turn are governed by the contours of the two great river estuaries.

“In the Delaware Bay, as you go upstream toward Philadelphia, the shore lines are converging in a kind of funnel shape, and so we see that amplifies sea level rise’s effects on the tides,” said Andrew Ross, a meteorologist then at Penn State University, but now at Princeton. “That amplification gets magnified the farther you go upstream.”

This article was originally published on Climate News Network and is shared under a Creative Commons license

About the author: Tim Radford, a founding editor of Climate News Network, worked for The Guardian for 32 years, for most of that time as science editor. He has been covering climate change since 1988.

Cover photo by Everaldo Coelho on Unsplash.
Pack your waders, we’re going… golfing! How climate change is threatening UK sports

Pack your waders, we’re going… golfing! How climate change is threatening UK sports

By Elisa Jiménez Alonso

A new report by the UK-based Climate Coalition finds that Open Championship venues like the St Andrews Old Course could be under water by the end of the 21st century even with a small increase in sea level rise. The report, called Game Changer: How climate change is impacting sports in the UK, finds that golf, football and cricket will face the most severe consequences. The Scottish skiing industry gets a very dark prediction as well, with the Climate Coalition saying it could collapse within the next 50 years.

“Climate change is already impacting our ability to play and watch the sports we love,” the Climate Coalition writes, and adds that extreme weather leads to declining participation and lost revenue.

The Open Championship, the UK’s only major professional golf tournament, is hosted on links courses including St Andrews, Royal Troon, Royal Birkdale, Hoylake, Royal Lytham & St Annes, Muirfield, Sandwich, Turnberry, Portrush, and 2018 venue Carnoustie. A links is the oldest form of golf courses and originated in Scotland. The name comes from the Scots language, meaning rising ground or ridge, and refers to an area of coastal sand dunes. As such, all links are at grave risk.

In Montrose, one of the world’s oldest golf courses with over 450 years, the third tee had to be sacrificed in 2017 due to reinforcement measures to protect the first and second tees from coastal erosion. In 2016, research done by the University of Dundee showed that in the past 30 years the North Sea has crept 70 metres towards Montrose.

“In a perfect storm we could lose 5-10 metres over just a couple of days and that could happen at pretty much any point.”

Director of the Montrose Golf Links explains in the report “As the sea rises and the coast falls away, we’re left with nowhere to go. Climate change is often seen as tomorrow’s problem – but it’s already eating away at our course. In a perfect storm we could lose 5-10 metres over just a couple of days and that could happen at pretty much any point.”

Other sports suffer too. In football, grassroots clubs are feeling the most severe impacts with bad weather reducing their playing seasons and flooding pitches. Cricket is also struggling, Cardiff-based club Glamorgan alone has lost 1,300 hours of cricket due to extreme weather and rainfall since 2000. The risk to the sport is so great it is already struggling to be commercially viable as less and less people get involved in the sport.

Interestingly enough, the solutions showcased in the report focus mostly on renewable energy and sustainability. While those are undoubtedly extremely important, it is clear sports need to adapt to changing climate conditions and build resilience to slow onset and sudden extreme weather events. Otherwise, economic losses could become an existential threat to the UK sports industry.

Download the Climate Coalition report Game Changer: How climate change is impacting sports in the UK by clicking here.

Visit the Climate Coalition website.

Cover photo by Andrew Rice on Unsplash
An X-factor in coastal flooding: Natural climate patterns create hot spots of rapid sea level rise

An X-factor in coastal flooding: Natural climate patterns create hot spots of rapid sea level rise

By Arnoldo Valle-Levinson, University of Florida and Andrea Dutton, University of Florida

For Americans who live along the east and Gulf of Mexico coasts, the end of the 2017 Atlantic hurricane season on Nov. 30 was a relief. Forecasters recorded 17 named storms, 10 of which became hurricanes. Six were major hurricanes (Category 3 or stronger), and three made landfall: Harvey in Texas, Irma in the Caribbean and Florida, and Maria in the Caribbean and Puerto Rico. It was the most costly season ever, inflicting more than US$200 billion in damages.

Many scientists have found evidence that climate change is amplifying the impacts of hurricanes. For example, several studies just published this month conclude that human-induced climate change made rainfall during Hurricane Harvey more intense. But climate change is not the only factor making hurricanes more damaging.

In a study we co-authored with our colleague Jon Martin, we showed that two converging natural climate processes created a “hot spot” from Cape Hatteras, North Carolina to Miami where sea levels rose six times faster than the global average between 2011 and 2015. We also showed that such hot spots have occurred at other points along the Eastern Seaboard over the past century. Now we see indications that one is developing in Texas and Louisiana, where it likely amplified flooding during Harvey – and could make future coastal storms more damaging.

Nearly every site measured has experienced an increase in coastal flooding since the 1950s. The rate is accelerating in many locations along the east and Gulf coasts. USEPA

Solving a salinity puzzle

Our work started when Jon Martin showed one of us (Arnoldo) salinity data from water trapped between sediments lining the floor of the Indian River Lagoon in east Central Florida. Here groundwater with zero salinity pools along the coast behind several barrier islands. Jon and his research team were analyzing changes in water chemistry and found that salinity had increased dramatically over the preceding decade. This suggested that saltwater was rapidly intruding into the lagoon.

This process is typically driven either by sea level rise or humans pumping fresh water from underground, or some combination of the two. Arnoldo consulted online data from the National Oceanic and Atmospheric Administration, and found that sea level rise had accelerated rapidly at nearby Trident Pier between 2011 and 2015. While global sea level has been rising at an average pace of about 1 foot per century, this site had recorded an increase of about 5 inches in a mere five years.

When Arnoldo shared this finding with Andrea, an international expert in past sea level rise, she was floored. These rates were ten times higher than the long-term rates of sea level rise along the Florida coastline. Further investigation showed that all tide gauges south of Cape Hatteras showed a similar uptick over the same period. This raised two questions: Had similar rates of rapid sea level rise previously been observed in the southeast United States? And what was causing this temporary acceleration?

Stations with positive sea level trends (yellow-to-red) are experiencing both global sea level rise and lowering or sinking of the local land. Stations illustrated with negative trends (blue-to-purple) are experiencing global sea level rise and a greater vertical rise in the local land, causing an apparent decrease in relative sea level. NOAA

Converging climate patterns

Previous work along the Atlantic coast had identified the area north of Cape Hatteras as vulnerable to accelerated rates of sea level rise, particularly in the context of climate change. Warming of the planet is expected to weaken the Gulf Stream, a powerful Atlantic Ocean current that pulls water away from the east coast and carries it northward. Slowing down the Gulf Stream leaves more water in place along the coastline, raising sea levels.

But this mechanism could not explain a jump of this magnitude in sea levels south of the Cape. Another previous study offered an additional clue. It proposed that the North Atlantic Oscillation (NAO), a seesaw pattern in air pressure over different regions of the North Atlantic Ocean, could explain the shift in the position of short-term variations in sea level rise.

Shifts in the NAO alter the position of the jet stream, wind patterns and storm tracks, all of which affect the distribution of water in the North Atlantic basin. Ultimately, the cumulative effects of NAO on the ocean determine whether water will pile up to the north or south of Cape Hatteras. Thus, water piled up preferentially to the north of Cape Hatteras in the period 2009-2010, and to the south from 2011 to 2015.

When the NAO is in its positive phase (left), the contrast between high pressure over the Azores and low pressure in the far north Atlantic is stronger than normal, which leads to mild storms over northern Europe and drying over the Mediterranean. But when the contrast is lower than normal, the NAO enters its negative phase (right), leading to cold, dry weather in northern Europe and wet conditions across the south. UCAR, CC BY-ND

This NAO-related mechanism explained where sea level accelerations might occur along the Atlantic coast, but did not seem to explain their timing. We filled in the blanks by examining tide gauge records over the last century along the entire U.S. Atlantic coast. This review showed that the timing of short-term sea level accelerations, lasting one to several years, was correlated with the accumulated signal of another recurring climate pattern: The El Niño Southern Oscillation, or ENSO, which is the result of an oscillation of atmospheric pressure in the Tropical Pacific Ocean basin.

Although ENSO occurs in the Pacific, its effects propagate across North America, altering air temperatures and wind regimes in the eastern United States. These changes in wind distributions can affect water transport in the North Atlantic Ocean, causing it to build up along the U.S. Eastern Seaboard at times. Other scientists have shown that this transport ultimately determines the timing of short-term accelerations in sea-level rise along the U.S. Atlantic coast.

In summary, we found that short-term accelerations in sea level rise have repeatedly occurred over the last century, sometimes occurring south of Cape Hatteras and sometimes focused north of the Cape. These hot spots can exceed rates of 4 inches in five years, and can occur anywhere along the U.S. Atlantic coast. They form when the accumulated signals of ENSO and the NAO converge, displacing seawater toward the coastline.

A wild card for coastal flooding

Our research has serious implications for coastal planners. Global warming is raising sea levels along the entire Atlantic coast, and communities should be preparing for it. In addition, our findings show that sea level can rise and fall around this level by more than 4 inches over a five-year period, due to variability in ocean-atmosphere interactions in the Pacific and Atlantic ocean basins. This variability can occur over the course of five to 10 years.

These hot spots amplify the severity of coastal flooding that is already occurring from storms and king tides. Residents between Charleston, South Carolina and Jacksonville, Florida – a stretch where sea levels are at least 4 inches (10 centimeters) higher now then they were in 2010 – have found this out the hard way.

Miami Beach residents are coping with dramatic increases in flooding driven by sea level rise.

The ConversationNow we are looking at data from the Gulf of Mexico, where tide stations are also showing water levels which are typically higher than predicted. The increase along Florida’s Gulf coast is past its peak, but Texas and Louisiana are still seeing an acceleration in sea level rise. Accelerations in sea level rise are hard to predict, and it is unclear whether they will become more serious over time. But they make it even more urgent for coastal communities to take sea level rise seriously today.

Arnoldo Valle-Levinson, Professor of Civil and Coastal Engineering, University of Florida and Andrea Dutton, Assistant Professor of Geology, University of Florida. This article was originally published on The Conversation. Read the original article.

Cover photo by Chris Coudron on Unsplash.
Video: How Greenland is trying to embrace climate change

Video: How Greenland is trying to embrace climate change

By Elisa Jiménez Alonso

The effects of climate change are very visible in Greenland. The ice cap is shrinking, glaciers are receding, the flora and fauna is changing. Amidst these environmental changes are Greenland’s people, and many of them are embracing rising temperatures.

Warmer temperatures are increasing fish stocks in the region, and in the farming heartland the growing season has been extending. Meanwhile the melting of Greenland’s ice cap has accelerated severely with NASA estimating it now loses about 300 billion tonnes of ice each year. That is not only a great threat to Greenland’s ecosystem, but also contributes significantly to global sea level rise.

In this short documentary by ABC News Australia, Eric Campbell travels to Greenland and speaks to people about the changes they are witnessing and how they are adapting to them:

Cover photo by Filip Gielda on Unsplash
Climate change threatens Scotland’s historic sites

Climate change threatens Scotland’s historic sites

By Elisa Jiménez Alonso

A report released by Historic Environment Scotland (HES) identifies nearly a fifth of the almost 340 sites it oversees as being at very high risk of being badly damaged due to climate change. Another 70% of its sites are said to be at high risk in this first-of-its-kind study.

Climate and geological data from the Scottish Environment Protection Agency and British Geological Survey were combined with HES’s own site surveys to create detailed climate risk assessments of each site. These show that historic site, often already fragile and exposed, are at risk from increased flooding, coastal erosion, heavier winter precipitation and drier summers. The report states:

“Water is the most destructive agent of decay. On a large scale, heavy and intense rainfall can directly lead to flooding in a short time frame, which has the potential to cause catastrophic damage to all elements of the historic environment within reach of these potential flood zones.”

The 28 sites with the highest risk, which include Fort George near Inverness and the 800-year-old Incholm Abbey on Incholm Island, are at an “unacceptable level of risk exposure” which would require immediate adaptation measures. Other sites which received a red warning, like Edinburgh Castle which is at very high risk of landslides and groundwater flooding, received an amber rating because they are under constant supervision by HES.

The study is part of ongoing efforts “to develop best practice and integrate climate change actions into [HES’s] operations.” The HES was tasked by The Scottish Climate Change Adaptation Programme with quantifying heritage assets affected by climate change using GIS in order to create a climate change risk register for their properties.

The report could led to increased pressure on other conservation organisations like the National Trust to step up their research efforts and identify climate risks to their sites in order to protect them appropriately.

Download and read the full report on HES’s website:

Cover photo by Timo Newton-Syms: Incholm island and former Augustine abbey in the Firth of Forth, Scotland (CC BY-SA 2.0)
Global wildfires of 2017 depict a fiery new normal

Global wildfires of 2017 depict a fiery new normal

By Georgina Wade

With 2017 breaking an unprecedented climate record of being the hottest non-El Niño year in history that included intense heat waves and wildfires worldwide, it seems that climate change has set the world ablaze.

An analysis carried out by World Weather Attribution points to human-caused climate change as the culprit behind extreme heatwaves that saw deadly forest fires blazing worldwide throughout 2017.

Europe’s forest fires more than doubled by late July, affecting an area twice the size of Luxembourg. According to the European Commission, fires broke out destroying over 902,000 hectares of land between France, Italy, Croatia, Spain, Greece and Portugal.

Portugal fires burnt 520,000 hectares of forest, representing nearly 60 percent of the total area burnt in the entire European Union in 2017. 64 people were killed, making 2017 the deadliest year on record for forest fires in the country.

Source: European Forest Fire Information System (EFFIS)

The United States also experienced a historically active wildfire season with California declaring 2017 as the most destructive fire season in the state. Five of California’s most destructive wildfires on record occurred in 2017, destroying more than 10,9800 structures including homes, outbuildings and commercial properties. It is estimated that a total of 9,133 fires erupted, turning more than 1,248,600 acres of forests, vineyards and farmland into barren lands.

The Thomas fire was first reported in early December and quickly became the largest wildfire on record in California, burning for more than a month before it was fully contained on 12 January. Destroying over 281,893 acres, the estimated damage of the fire is over $177 million.

Additionally, other Western states found themselves battling historical wildfires with Oregon’s annual disaster cost spiking to $454 million in 2017, the most so far this century.  In neighbouring Montana, two fires alone burned over 100,000 acres each with severe drought bringing about a premature start to the wildfire season.

And this year’s wildland fire forecasts are not looking promising. The National Interagency Fire Center’s Predictive Services unit predicts an active fire season. Westerly flow could produce overall warmer and drier than average conditions in March and April for the Northwest and Great Lakes regions of the United States. Additionally, the report finds that High dead fuel loadings left behind by hurricanes Harvey, Irma and Maria will continue to pose unique fire danger concerns for coastal Texas, Florida, and Puerto Rico.

And with large areas of Australia currently hitting life-threatening temperatures and bushfires raging out of control near Melbourne, it seems that 2018 is picking up right where 2017 left off.

Source: National Interagency Fire Center’s Predictive Services

Cover photo by Scott L/Flickr (CC BY 2.0): The La Tuna Fire burns in the Verdugo Mountains in the Eastern San Fernando Valley of Los Angeles, CA. 1 Sept 2017.
2017: The United States’ Year of Billion Dollar Weather and Climate Disasters

2017: The United States’ Year of Billion Dollar Weather and Climate Disasters

By Georgina Wade

It turns out that 2017 was uniquely disastrous to the United States in more ways than one with the National Oceanic and Atmospheric Administration (NOAA) attributing a cumulative damage amount of $306.2 billion to 16 separate disaster events, a record previously held in 2005.

Hurricanes Harvey, Irma and Maria combined with 2017’s extreme wildfires make up four of the 16 weather and climate disasters with losses exceeding $1 billion each. Overall, these events resulted in the deaths of 362 people and had significant economic effects on the areas impacted.

Source: NOAA National Centers for Environmental Information (NCEI)

Since 1980, the U.S. has sustained 219 billion-dollar climate-related disasters with cumulative costs exceeding $1.5 trillion dollars. From 1980-2016, the annual average number of billion-dollar events was 5.8 whereas the most recent five years (2013-2017) saw an annual average of 11.6 events.

With $135 billion expected in insured losses, 2017 is also a costly year for the insurance industry, giving reinsurance companies such as MunichRe a primary role in helping people and communities rebuild in the wake of natural catastrophes.

Source: Munich Re NatCatSERVICE

Acting as an insurer for insurance companies, MunichRe utilises NOAA’s National Centers for Environmental Information (NCEI) to understand the probability of these natural disasters and sell premiums to insurance companies in exchange for coverage.

As insurance companies are often required by law to buy reinsurance because they lack the capital resources to pay out if there is a major disaster, companies like MunichRe have a unique incentive to understand and predict these trends.

Additionally, this understanding has resulted in reinsurers being at the forefront of warning businesses and the public about the rise in extreme weather events due to climate change.

A MunichRe release in September 2010 noted it had analysed its catastrophe database, “the most comprehensive of its kind in the world” and concluded, “the only plausible explanation for the rise in weather-related catastrophes is climate change.

NOAA researcher Adam B. Smith agrees, citing climate change as a primary culprit in the frequency of these severe weather and climate events.

“Climate change is playing an increasing role in the increasing frequency of some types of extreme weather that lead to billion-dollar disasters,” Smith wrote in a blog post. “Most notably the rise in vulnerability to drought, lengthening wildfire seasons and the potential for extremely heavy rainfall and inland flooding events are most acutely related to the influence of climate change.”

Cover photo by Marcus Kauffman on Unsplash: Big Fall Creek Road, Lowell, United States, during the Jones Fire in August 2017.

Learn more about the role of NOAA’s NCEI data by clicking here and watching our video below:

2017: the year in extreme weather

2017: the year in extreme weather

By Andrew King, University of Melbourne

Overall 2017 will be the warmest non-El Niño year on record globally, and over the past 12 months we have seen plenty of extreme weather, both here in Australia and across the world. Here I’ll round up some of this year’s wild weather, and look forward to 2018 to see what’s around the corner.

Drought and flooding rains… again

It feels as if Australia has had all manner of extreme weather events in 2017. We had severe heat at both the start and end of the year. Casting our minds back to last summer, both Sydney and Brisbane experienced their hottest summers on record, while parts of inland New South Wales and Queensland endured extended periods of very high temperatures.

More recently Australia had an unusually dry June and its warmest winter daytime temperatures on record. The record winter warmth was made substantially more likely by human-caused climate change.

The end of the year brought more than its fair share of extreme weather, especially in the southeast. Tasmania had by far its warmest November on record, beating the previous statewide record by more than half a degree. Melbourne had a topsy-turvy November with temperatures not hitting the 20℃ mark until the 9th, but a record 12 days above 30℃ after that.

November was rounded off by warnings for very severe weather that was forecast to strike Victoria. Melbourne missed the worst of the rains, although it still had a very wet weekend on December 2-3. Meanwhile, northern parts of the state were deluged, with many places recording two or three times the December average rainfall in just a couple of days.

Hurricane after hurricane after hurricane…

Elsewhere in the world there was plenty more headline-worthy weather. The Atlantic Ocean had a particularly active hurricane season, with several intense systems. Hurricane Harvey struck Texas and its slow trajectory resulted in record-breaking rainfall over Houston and neighbouring areas.

Then Hurricanes Irma and Maria, both of which reached the strongest Category 5 status, brought severe weather to the Caribbean and southeastern United States just a couple of weeks apart. Island nations and territories in the region are still recovering from the devastation.

Around the same time, the Indian subcontinent experienced a particularly wet monsoon season. Flooding in India, Pakistan, Bangladesh, and Nepal killed more than 1,000 people and affected tens of millions more. Other parts of the world experienced their own severe weather events. Whether it was summer heat in Europe or wildfires in California, 2017 dished up plenty of extremes.

In many cases, especially for heat extremes, we can rapidly identify a human influence and show that climate change is increasing the frequency and intensity of such events. For other weather types, like the very active hurricane season and other extreme rain or drought events, it is harder (but not always impossible) to work out whether it bears the fingerprint of climate change.

What’s in store for 2018?

The main problem when trying to offer an outlook is that extreme weather is hard to predict, even on the scale of days or weeks in advance, let alone months.

For Australia, with a weak La Niña in the Pacific, there are few clear indications of what the rest of the summer’s weather will bring. There is a suggestion that we can expect a slightly wetter than average start to the year in parts of the southeast, along with warmer than average conditions for Victoria and Tasmania. Beyond that it is anyone’s guess.The La Niña is also likely to mean that 2018 won’t be a record hot year for the globe. But it’s a safe bet that despite the La Niña, 2018 will still end up among the warmest years on record, alongside every other year this century. Rising global average temperatures, along with our understanding of the effect of greenhouse gas emissions, are one of our clearest lines of evidence for human-caused climate change.

The ConversationSo it’s hard to say much about what extreme weather we’ll experience in 2018, other than to say that there’s likely to be plenty more weather news to wrap up in a year’s time.

Andrew King, Climate Extremes Research Fellow, University of Melbourne. This article was originally published on The Conversation. Read the original article.

Cover animation by NOAA (public domain): A Rainbow Infrared graphic of Hurricane Maria from 05:45 UTC to 12:45 UTC 20 September 2017 from sensors on the GOES Floater satellite.