Coupeville is one of the oldest towns in Washington state. It’s a ­popular destination in summer, but on a winter’s day, Kāholo and crew had the anchorage all to themselves.
Tor Johnson

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I’m no Ernest Shackleton. I live in Hawaii, and I love the warm weather and clear blue waters of the tropics. Having done a little high-latitude sailing, I have to admit that freezing weather is not my favorite. My boat doesn’t even have a heater.

Yet here I was with Tracy, a surfing friend from Hawaii, ripping down Puget Sound at 12 knots under spinnaker, in the dead of winter. I had on about 10 layers, two puffy jackets, gloves, boots and a hat. I also had a huge smile on my face.

This was shaping up to be an ideal adventure, filled with solitude and unexpected experiences. It was also some of the best sailing I’d done on my Jeanneau 509, Kāholo. And it had all started with simple necessity: I had to move the boat to get new canvas.

Smooth sailing for Kāholo between the wooded islands of Puget Sound.
Tor Johnson

In 2021, I had sailed ­new-to-me Kāholo 5,000 miles, across the Atlantic and the length of the Caribbean, from Portugal to Panama (“That’s Not Going To Happen,” CW Nov/Dec 2022). While soaking under the torrential rains of Panama, I realized I definitely needed new canvas. Once we got to the Pacific Northwest, I learned that Iverson’s Canvas in Olympia, Washington, had a yearslong waiting list. And its team would not travel to your boat. Like the Soup Nazi in Seinfeld said, “No soup for you!” Unless you were ­prepared to travel.

Olympia is on the South Sound near Tacoma, 80 miles south of my winter berth in La Conner, near the San Juan Islands. Although I managed to secure a spot on Iverson’s busy schedule, the only date its team could do the work was in mid-February, the coldest month of the year.

Well aware of the shifting weather systems in Puget Sound, I stacked things in my favor by leaving plenty of time to choose a weather window. As luck would have it, a high-­pressure system was set to fill in, bringing a favorable, but very cold, northerly wind. To get ready for the next day’s northerlies, Tracy and I made a short sail out to the historic town of Coupeville on Whidbey Island, where we spent time in a warm pub with the colorful local crowd that had replaced the summer tourists. Well-fortified against the cold, we paddled back out to lonesome Kāholo, the only anchor light in the anchorage.

“Michelin Man” Johnson steers south through Admiralty Inlet, warmed by several puffy jackets and gloves.
Tor Johnson

Leaving Coupeville early, we had a serene reach south in calm water, all alone, jibing back and forth across Possession Sound under an asymmetrical spinnaker. It was challenging sailing in shifting winds, amid evergreen-­covered islands down Whidbey, the second-longest island in the United States, after New York’s Long Island.

The wind began to build as we neared the bottom of Whidbey. The helm felt lively. Somewhere around freezing, the wind sent a chill right through me. Adding another puffy jacket at the helm, I was quite comfortable but looked like the Michelin Man.

We blew right past the mooring I’d had in mind for the end of the short winter day, not to mention the alternate destinations I’d marked off in case the weather or the gear failed to cooperate. This was no ordinary sail, and we were having too much fun. We continued south toward Seattle.

Reaching south under spinnaker across the calm, cold waters of Possession Sound.
Tor Johnson

Passing the southern tip of Whidbey Island, we sailed into the comparatively open water of Admiralty Inlet. Both the seas and the wind began to build. Now we were reaching at 12 knots with more than 20 knots of apparent wind. This was the upper limit for the spinnaker. The boat was ­handling well, but I could feel the rudder loading up as the boat leapt through the following seas. Rounding up in this wind with the spinnaker would mean taking it down in pieces. Breaking seas to windward alerted me that the wind was still building in the exposed waters of Admiralty Inlet. As the saying goes, any fool can put up a sail, but it takes a sailor to know when to take one down—and I’d ­apparently left it a bit late.

“Tracy!” I called out. “We need to get that spinnaker down. Now!” 

As Tracy hustled forward, I brought the boat downwind to hide the spinnaker behind the main. Tracy tried to douse the sail, but the sock refused to come down. The spinnaker sock lines had become tangled after so many jibes. I managed to balance the boat on a deep reach, with the seas slewing her around and the spinnaker flailing behind the main. I set the autopilot, praying we wouldn’t wrap the sail around the forestay, and jumped forward to help. We managed to untangle the lines while the autopilot miraculously kept us safely off the wind. The sock ­finally slid over the unruly beast and we dropped the sail to the deck with a sigh of relief. After that battle, we were no longer cold. The wind increased to the point to where the working jib was now plenty of sail, and we surfed south to Port Blakely, just across Puget Sound from Seattle on Bainbridge Island.

A Washington state ferry passes in front of Mount Baker. They move faster than you think, and they don’t give way easily.
Tor Johnson

We arrived as the sun set and the lights of Seattle came alive in a purple sky. We could see the huge marinas of Elliott and Shilshole bays, housing thousands of boats. Yet we were alone, swinging at anchor in a quiet cove at the end of a perfect weekend sailing day. Finally, one other sailboat joined us: a singlehander on his 30-foot Wauquiez. 

With the setting sun, temperatures dipped well below freezing. Luckily, we had thick down comforters on the bunks to keep us warm. In the morning, I found water pooling on the floorboards, something no captain wants to see. Assuming we had a freshwater leak in one of the pressurized lines, I pulled off panels to reveal the hullsides. They were running with water. In freezing temperatures, comparatively warm moist air inside the cabin condenses on the cold hull of the boat “like a cold can of soda on a hot day,” as one sailor described it. I immediately invested in a dehumidifier for use at the dock. The proper solution while underway would, of course, be a diesel heating system. 

The northerlies were still blowing the next day, and we raised the spinnaker again, doing an outside jibe back and forth down serpentine Colvos Passage to Gig Harbor. For an outside jibe, I bring the boat directly downwind, jibe the main to put the boat wing on wing, and then completely release the working spinnaker sheet, letting the spinnaker flag in front of the boat. I then turn the boat through the wind, onto the new tack, and haul in the leeward spinnaker sheet, which is led around the bow on the outside. I can do this singlehanded, and it works like a charm as long as the sheets don’t get snagged on anything. Sadly, they often do, which requires a trip to the foredeck to unsnag them.

Emiliano Marino, of The Artful Sailor, keeps the traditions of ancient sailors alive at Port Townsend.
Tor Johnson

Gig Harbor was where we’d planned to meet the team from Iverson’s Canvas. A lively harbor town shadowed by Mount Rainier—with several marinas, a fishing fleet, a strong paddling scene, and lots of maritime history—Gig Harbor was named in the 1800s for Capt. Wilson’s gig, or rowboat, brought into the narrow entrance for shelter. The town is home to Gig Harbor Boat Works, which builds traditional gigs from modern materials.

It was amazing to watch Kyle and Mike, two guys from Iverson’s. They installed custom, large-diameter stainless, and patterned the entire dodger and Bimini top with plastic sheeting, all in a day. They said it would be two weeks for me to receive the dodger and Bimini top, but they were back a day early. The new dodger transformed the cockpit, with better visibility and clear windows. It felt as though I’d been upgraded to an ocean-view home after cowering under an old tent for years. It wasn’t cheap, but it was money well spent.

As luck would have it, sailing north back up Puget Sound was also a downwind run. Southeasterlies are quite common in winter, often associated with the approach of a low-pressure system. This was exactly the case I encountered: An approaching low was sending me 15-knot southeasterlies. I jibed back and forth up the sound, this time singlehanding because Tracy had flown back to Hawaii. Often, I would tangle the sheets on some obstacle on deck or on the anchor, and I’d need to hustle forward to free it. On my last jibe across Admiralty Inlet, on a layline for Port Townsend, I noticed the unmistakable T-shaped mast of a submarine steaming at me en route to the naval yard at Bremerton. Two oceangoing tugs and two US Coast Guard vessels were in escort. Soon, the Coast Guard politely hailed me: “Sailing vessel Kāholo, I see that you are making tracks for Marrowstone Point. We request that you keep as close as you feel safe to the shore. We will be turning right, into your path.” Good thing I was on a layline, with good speed, and didn’t plan another jibe. The consequences of something going wrong were too great.

Tribal art on Blake Island features a salmon, the source of life for the people of the Northwest.
Tor Johnson

An old friend, veteran bluewater sailing instructor John Neal with Mahina Expeditions, met me at the dock at Port Townsend. He showed me around the bustling boatyards and introduced me to his favorite sailmaker, Port Townsend Sails, and riggers, Port Townsend Rigging. These are family operations where attention to detail and craftsmanship are the rule. John says that he can get 50,000 to 55,000 miles (two circumnavigations) on a single main and jib built by the craftspeople at Port Townsend Sails, who, by the way, are all women. 

I set out on foot to see the boatyards at Port Townsend, the premier wooden-boat building and repair region on the West Coast. It’s a dynamic place where the next generation of shipwrights learns traditional skills at places such as the Northwest School of Wooden BoatBuilding. I wandered around the yards, amazed at vessels like the 133-foot San Francisco bar pilot cutter Adventuress, built in 1913 and still sailing here. 

Port Townsend is famous for its annual wooden-boat show, but what seems to have escaped worldwide notice is that Kirsten Neuschäfer, the South African sailor who recently became the first woman to win the Golden Globe round-the-world race, sailed a Port Townsend boat: a 36-foot, 1988 fiberglass-hulled version of a traditional 1930s design built by Cape George Marine Works. Her boat was among only three boats to finish the grueling race without pause for repairs, and it survived 235 days at sea around the tempestuous Great Capes—and with Neuschäfer managing to rescue a skipper whose boat had sunk.

Continuing my stroll through Port Townsend on this cold, blustery afternoon, and seeing a small sign advertising “sails and canvas built and repaired” on an old wooden building in the harbor, I ducked into a shop called The Artful Sailor. Engulfed by the smell of tar, hemp and linseed oil, I found Emiliano Marino and Pami-Sue “Salty Sue” Alvarado practicing the ancient art of marlinspike seamanship. The late-afternoon light streaming in through the windows made it look like a scene from an old Dutch painting.

Only in Port Townsend could a sailor encounter a nuclear submarine, see a 1913 schooner and meet a couple practicing traditional marlinspike splicing, all in the same day.

Unfortunately, my luck ran out with the weather, and I sailed the 30 miles up to Deception Pass and to Kāholo’s La Conner slip in full foul-weather gear, in cold, drizzling rain and variable winds. The ending was a bit of a letdown, but overall, this had been an unforgettable voyage, precisely because it had happened in the dead of winter.

Not that I am planning any Shackleton-esque small-boat crossings in the Antarctic, but at least now I understand the beauty of a winter’s sail. Next on the my shopping list? A diesel heater.

Tor Johnson is an award-­winning photographer and writer who has shot 16 covers of CW, so far. He grew up sailing the world with his family.

The post A Winter’s Sail | Cruising World appeared first on DAILY SAN FRANCISCO BAY NEWS.

As winters get warmer, tropical mosquitoes like Aedes aegypti move north, potentially increasing the spread of diseases like dengue, yellow fever, and zika. Photo by Muhammad Mahdi Karim Photo.

Notwithstanding the February cold snap in Texas and Louisiana, climate change is causing warmer winter weather across the southern United States, which is a golden opportunity for many tropical plants and animals to move north, according to a new study in the journal Global Change Biology.

Some of these species are welcome, such as sea turtles and the Florida manatee, which expand northward along the Atlantic coast.

Others, like the invasive Burmese python – in the Florida Everglades, the largest measured 18 feet, end-to-end – maybe less.

Insects, including mosquitoes, which transmit diseases such as West Nile virus, Zika, dengue and yellow fever, and beetles, which destroy native trees, are equally undesirable and among the fastest-spreading in warming areas.

“Quite a few mosquito species are expanding northward, as are forestry pests: bark beetles, the southern mountain pine beetle,” said Caroline Williams, associate professor of integrative biology at the University of California at Berkeley, and co-author of the paper. “In our study, we really focused on the US border where we are seeing this rapid transition from tropical to temperate. Changes in winter conditions are one of the main drivers, if not the main drivers, of the shift in distributions.”

That transition zone, north of which freezes occur every winter, has always been a barrier to species that evolved at more stable temperatures, said Williams, who specializes in insect metabolism – specifically, how winter freezes and snow affect species survival .

“For the vast majority of organisms, they die when they freeze,” she said. “Cold snap like the recent one in Texas might not happen for 30, 50, or even 100 years, and then you see these widespread mortality events where tropical species crawling north are suddenly repelled. But as return times get longer and longer for these extreme cold events, it enables tropical species to gain a foothold, and perhaps even for local populations to adapt so that they can tolerate more cold extremes in the future. “

The study, conducted by a team of 16 scientists led by the US Geological Survey (USGS), focused on the effects of winter warming on the movement of a wide range of cold-sensitive tropical plants and animals in the southern United States, in particular to the south The eight subtropical mainland US states: Florida, Alabama, Mississippi, Louisiana, Texas, New Mexico, Arizona, and California. Williams and Katie Marshall of the University of British Columbia at Vancouver jointly wrote the insect section for the study.

The team found that a number of tropical species, including insects, fish, reptiles, amphibians, mammals, grasses, shrubs, and trees, are expanding their range to the north. Among them are species native to the United States such as mangroves, which are tropical salt tolerant trees; and snook, a sport fish on the coast with warm water; and invasive species such as Burmese pythons, Cuban tree frogs, Brazilian pepper trees, and buffalo grass.

“We don’t expect a continuous process,” said USGS research ecologist Michael Osland, the study’s lead author. “There will be an expansion north, then a contraction with extremely cold events like the one that just happened in Texas, and then movement again. However, we expect tropization by the end of this century. ”

The authors document decades worth of changes in the frequency and intensity of extreme cold snaps in San Francisco, Tucson, New Orleans, and Tampa – all cities with temperature records dating back to at least 1948. In every city, they found, winter means temperatures have risen over time, the coldest winter temperatures have gotten warmer, and there are fewer days each winter when mercury drops below freezing.

For example, temperature records from San Francisco International Airport show that prior to 1980, each winter was typically several days below freezing. In the last 20 years there has only been one day with temperatures below freezing.

Changes already ongoing or anticipated in the home areas of 22 species of plants and animals from California to Florida include:

– Continuous displacement of temperate salt marsh plants by mangrove forests that are sensitive to the cold along the Gulf and South Atlantic coast. While this encroachment has occurred over the past 30 years with sea level rise, mangroves can also move inland, displacing temperate and freshwater forests.
Buffalo grass and other annual grasses that migrate to southwestern deserts and cause wildfire in native plant communities that have not evolved in association with frequent fire.
– The likelihood that tropical mosquitoes, which can transmit encephalitis, West Nile virus, and other diseases, will continue to expand, putting millions of people and wildlife at risk for these diseases.
– Likely southern pine beetle moving north with warming winters, a pest that can damage commercially valuable pine forests in the southeast.
– Disruption of recreational and commercial fishing due to changes in migration patterns and the movement of inshore fish to the north.

The changes are expected to result in the replacement of some of the temperate plant and animal communities found today in the southern United States with tropical communities.

“Unfortunately, the general story is that the species that do really well are the more general species – their hosts or food sources are very diverse or widespread, and they have a relatively large thermal tolerance so they can tolerate a wide range the terms, “said Williams. “And by definition, these are usually the pest species – that’s why they are pests: They are adaptable, widespread, and relatively undisturbed by changing conditions, while the more specialized or boutique species tend to decline when driven out of their relatively narrow niche. “

She warned that insect populations around the world are declining overall.

“We’re seeing an alarming decline in total numbers in natural areas, managed areas, national parks and tropical rainforests – worldwide,” she said. “While we are seeing some common pest species increasing, the overall pattern is that insects are declining extremely quickly.”

The authors suggest in-depth laboratory studies to learn how tropical species can adapt to extreme conditions and to show how extended intervals between cold spells affect plant and animal communities.

“It is hopeful that as climates, including winter climates, change, we must prepare for sweeping changes in the distribution of biodiversity as the climates, including winter climates, change, rather than heading towards the extinction of absolutely everything,” Williams said. “The actions we take over the next 20 years will be critical to determining our trajectory. In addition to obvious changes like reducing our carbon footprint, we need to protect and restore habitat for insects. Individuals can have their own habitat create backyards for insects by growing native plants that aid pollinators and other native insects – these are little things humans can do that can be important in creating corridors for species to move through our highly fragmented habitats. “

Robert Sanders writes for the UC Berkeley News Center.

The post Lake County Information,California – Tropical species are shifting northward as winters heat appeared first on DAILY SAN FRANCISCO BAY NEWS.

Despite last month’s cold snap in Texas and Louisiana, climate change is leading to warmer winter weather throughout the southern United States and providing a unique opportunity for many tropical plants and animals to migrate north. That’s according to a new study published this week in the journal Global Change Biology.

Some of these species are welcome, such as sea turtles and the Florida manatee, which expand northward along the Atlantic coast. Others, like the invasive Burmese python – in the Florida Everglades, the largest at 18 feet (end-to-end) in length – may be less affected.

Insects, including mosquitoes, which transmit diseases such as West Nile virus, Zika, dengue and yellow fever, and beetles that destroy native trees, are equally undesirable and among the fastest-spreading in warming areas.

“Quite a few mosquito species are expanding northward, as are forestry pests: bark beetles, the southern mountain pine beetle,” said Caroline Williams, associate professor of integrative biology at the University of California at Berkeley, and co-author of the paper. “In our study, we really focused on the border in the US where we get this rapid transition from tropical to temperate. Changes in winter conditions are one of the main drivers, if not the main driver, of shifting distributions. “

This transition zone, north of which freezes occur every winter, has always been a barrier to species that evolved at more stable temperatures, said Williams, who specializes in insect metabolism – specifically, how winter freezes and snow affect species survival .

“For the vast majority of organisms, they die when they freeze,” she said. “Cold spells like the recent one in Texas might not happen for 30, 50, or even 100 years, and then you see these widespread mortality events where tropical species crawling north are suddenly pushed back. However, as the return times for these extreme cold events become longer, tropical species can gain a foothold and local populations may be able to adapt to tolerate more cold extremes in the future. “

The study, conducted by a team of 16 scientists led by the US Geological Survey (USGS), focused on the effects of winter warming on the movement of a wide range of cold-sensitive tropical plants and animals in the southern United States, in particular to the south The eight subtropical mainland US states: Florida, Alabama, Mississippi, Louisiana, Texas, New Mexico, Arizona, and California. Williams and Katie Marshall of the University of British Columbia at Vancouver jointly wrote the insect section for the study.

The team found that a number of tropical species, including insects, fish, reptiles, amphibians, mammals, grasses, shrubs, and trees, are expanding their range to the north. Among them are species native to the United States such as mangroves, which are tropical salt tolerant trees; and snook, a hot water sport fish on the coast; and invasive species such as Burmese pythons, Cuban tree frogs, Brazilian pepper trees, and buffalo grass.

“We don’t expect a continuous process,” said USGS research ecologist Michael Osland, the study’s lead author. “There will be an expansion north, then a contraction with extremely cold events like the one that just happened in Texas, and then movement again. However, we expect tropization by the end of this century. “

The authors document decades worth of changes in the frequency and intensity of extreme cold snaps in San Francisco, Tucson, New Orleans, and Tampa – all cities with temperature records dating back to at least 1948. In every city, they found, winter means temperatures have risen over time, the coldest winter temperatures have gotten warmer, and there are fewer days each winter when mercury drops below freezing.

For example, temperature records from San Francisco International Airport show that prior to 1980, each winter was typically several days below freezing. In the last 20 years there has only been one day with temperatures below freezing.

Changes already ongoing or anticipated in the home areas of 22 species of plants and animals from California to Florida include:

• Continuous displacement of temperate salt marsh plants by cold-sensitive mangrove forests along the Gulf and South Atlantic coast. While this encroachment has occurred over the past 30 years with sea level rise, mangroves can also move inland, displacing temperate and freshwater forests.
• Buffalo grass and other annual grasses that migrate to southwestern deserts and cause wildfire in native plant communities that have not evolved in association with frequent fire.
• The likelihood that tropical mosquitoes, which can transmit encephalitis, West Nile virus, and other diseases, will continue to expand, putting millions of people and wildlife at risk for these diseases.
• Likely northern pine beetle movement with warming winters, a pest that can damage commercially valuable pine forests in the southeast.
• Disruption of recreational and commercial fishing due to changes in migration patterns and the movement of inshore fish to the north.

The changes are expected to result in the replacement of some of the temperate plant and animal communities found today in the southern United States with tropical communities.

“Unfortunately, the general story is that the species that do really well are the more general species – their hosts or food sources are very different or widespread, and they have a relatively large thermal tolerance so they can tolerate a wide variety Conditions, ”said Williams. “And by definition, these are usually the pest species – that’s why they are pests: They are adaptable, widespread, and relatively undisturbed by changing conditions, while the more specialized or boutique species tend to decline when driven out of their relatively narrow niche. “

She warned that overall insect populations are falling worldwide.

“We’re seeing an alarming decline in total numbers in natural areas, managed areas, national parks and tropical rainforests – worldwide,” she said. “While we are seeing some common pest species increasing, the overall pattern is that insects are declining extremely quickly.”

The authors suggest in-depth laboratory studies to learn how tropical species can adapt to extreme conditions and to show how extended intervals between cold spells affect plant and animal communities.

“It is hopeful that as climates, including winter climates, change, we must prepare for sweeping changes in the distribution of biodiversity as the climate changes, including winter climates,” said Williams. “The actions we take over the next 20 years will be critical to determining our trajectory. In addition to obvious changes like reducing our carbon footprint, we need to protect and restore habitat for insects. Individuals can create habitat for insects in their own backyards by cultivating native plants that aid pollinators and other native insects. These are little things that humans can do that can be important in creating corridors for species to move through our very fragmented habitats. “

The post Tropical Species Are Shifting Northward In US As Winters Heat appeared first on DAILY SAN FRANCISCO BAY NEWS.

Despite last month’s cold snap in Texas and Louisiana, climate change is leading to warmer winter weather throughout the southern United States and providing a unique opportunity for many tropical plants and animals to migrate north. That’s according to a new study published this week in the journal Global Change Biology.

Some of these species are welcome, such as sea turtles and the Florida manatee, which expand northward along the Atlantic coast. Others, like the invasive Burmese python – in the Florida Everglades, the largest at 18 feet (end-to-end) in length – may be less affected.

Insects, including mosquitoes, which transmit diseases such as West Nile virus, Zika, dengue and yellow fever, and beetles that destroy native trees, are equally undesirable and among the fastest-spreading in warming areas.

“Quite a few mosquito species are expanding northward, as are forestry pests: bark beetles, the southern mountain pine beetle,” said Caroline Williams, associate professor of integrative biology at the University of California at Berkeley, and co-author of the paper. “In our study, we really focused on the border in the US where we get this rapid transition from tropical to temperate. Changes in winter conditions are one of the main drivers, if not the main driver, of shifting distributions. “

This transition zone, north of which freezes occur every winter, has always been a barrier to species that evolved at more stable temperatures, said Williams, who specializes in insect metabolism – specifically, how winter freezes and snow affect species survival .

A 2017 photo of USGS researchers handling a Burmese python in the Florida Everglades. The snake has decimated communities of mammals, birds, and other animal communities in the Everglades. (Courtesy photo of USGS)

“For the vast majority of organisms, they die when they freeze,” she said. “Cold spells like the recent one in Texas might not happen for 30, 50, or even 100 years, and then you see these widespread mortality events where tropical species crawling north are suddenly pushed back. However, as the return times for these extreme cold events become longer, tropical species can gain a foothold and local populations may be able to adapt to tolerate more cold extremes in the future. “

Fewer days below freezing enable tropical invasions

The study, conducted by a team of 16 scientists led by the US Geological Survey (USGS), focused on the effects of winter warming on the movement of a wide range of cold-sensitive tropical plants and animals in the southern United States, in particular to the south The eight subtropical mainland US states: Florida, Alabama, Mississippi, Louisiana, Texas, New Mexico, Arizona, and California. Williams and Katie Marshall of the University of British Columbia at Vancouver jointly wrote the insect section for the study.

A monarch caterpillar. Monarchs cannot tolerate freezing weather and usually winter in Mexico. Thanks to milder winter temperatures, they now hibernate in California. (UC Berkeley photo by Noah Whiteman)

The team found that a number of tropical species, including insects, fish, reptiles, amphibians, mammals, grasses, shrubs, and trees, are expanding their range to the north. Among them are species native to the United States such as mangroves, which are tropical salt tolerant trees; and snook, a hot water sport fish on the coast; and invasive species such as Burmese pythons, Cuban tree frogs, Brazilian pepper trees, and buffalo grass.

“We don’t expect a continuous process,” said USGS research ecologist Michael Osland, the study’s lead author. “There will be an expansion north, then a contraction with extremely cold events like the one that just happened in Texas, and then movement again. However, we expect tropization by the end of this century. ”

The authors document decades worth of changes in the frequency and intensity of extreme cold snaps in San Francisco, Tucson, New Orleans, and Tampa – all cities with temperature records dating back to at least 1948. In every city, they found, winter means temperatures have risen over time, the coldest winter temperatures have gotten warmer, and there are fewer days each winter when mercury drops below freezing.

For example, temperature records from San Francisco International Airport show that prior to 1980, each winter was typically several days below freezing. In the last 20 years there has only been one day with temperatures below freezing.

A map showing North America’s transition zone from tropical to temperate. Red, orange, and yellow represent the more tropical zones, and blue indicates the more temperate zones, based on the coldest recorded temperature for each area between 1980 and 2009. Photos show some cold-sensitive plants and animals with northern range limits determined by winter cold temperature extremes. (Map courtesy of USGS)

Changes already ongoing or anticipated in the home areas of 22 species of plants and animals from California to Florida include:

• Continuous displacement of temperate salt marsh plants by cold-sensitive mangrove forests along the Gulf and South Atlantic coast. While this encroachment has occurred over the past 30 years with sea level rise, mangroves can also move inland, displacing temperate and freshwater forests.
• Buffalo grass and other annual grasses that migrate to southwestern deserts and cause wildfire in native plant communities that have not evolved in association with frequent fire.
• The likelihood that tropical mosquitoes, which can transmit encephalitis, West Nile virus, and other diseases, will continue to expand, putting millions of people and wildlife at risk for these diseases.
• Likely northern pine beetle movement with warming winters, a pest that can damage commercially valuable pine forests in the southeast.
• Disruption of recreational and commercial fishing due to changes in migration patterns and the movement of inshore fish to the north.

Tropical species can displace natives

The changes are expected to result in the replacement of some of the temperate plant and animal communities found today in the southern United States with tropical communities.

The southern pine beetle (Dendroctonus frontalis), native to the forests of the southern United States, Mexico, and Central America, continues to move north as winter temperatures rise with climate change. The bark beetles leave behind destroyed pine forests.

“Unfortunately, the general story is that the species that do really well are the more general species – their hosts or food sources are very different or widespread, and they have a relatively large thermal tolerance so they can tolerate a wide variety Conditions, ”said Williams. “And by definition, these are usually the pest species – that’s why they are pests: They are adaptable, widespread, and relatively undisturbed by changing conditions, while the more specialized or boutique species tend to decline when driven out of their relatively narrow niche. “

She warned that overall insect populations are falling worldwide.

“We’re seeing an alarming decline in total numbers in natural areas, managed areas, national parks and tropical rainforests – worldwide,” she said. “While we are seeing some common pest species increasing, the overall pattern is that insects are declining extremely quickly.”

The authors suggest in-depth laboratory studies to learn how tropical species can adapt to extreme conditions and to show how extended intervals between cold spells affect plant and animal communities.

“It is hopeful that as climates, including winter climates, change, we must prepare for sweeping changes in the distribution of biodiversity as the climate changes, including winter climates,” said Williams. “The actions we take over the next 20 years will be critical to determining our trajectory. In addition to obvious changes like reducing our carbon footprint, we need to protect and restore habitat for insects. Individuals can create habitat for insects in their own backyards by cultivating native plants that aid pollinators and other native insects. These are little things that humans can do that can be important in creating corridors for species to move through our very fragmented habitats. “

The post Tropical species are transferring northward as winters heat appeared first on DAILY SAN FRANCISCO BAY NEWS.