Lake Mead at Hoover Dam, 1998 (photo from Wikimedia Commons)
Lake Mead at Hoover Dam, 2015 (photo from Wikimedia Commons)
It’s hard to remember what we worried about before the coronavirus, but long term water crises provoked by climate change are still chugging along in the U.S. West. The most troubling of these is looming at the Colorado River, the water source for over 40 million people.
Many of the seven western states in the Colorado River watershed are suffering under severe to extreme drought. Of course it affects the river.
Albedo is a reflectivity measure of various surfaces as they reflect sunlight back into space. Snow and ice have high albedo, bare ground and trees have low albedo. Melting snow and ice expose low albedo ground so the temperature rises. As the temperature rises more snow and ice melt. This climate change feedback loop is affecting the Colorado River.
The two photos at top span 22 years on the Colorado River at Lake Mead where Hoover Dam holds back the river. The amount of water in the lake is highly controlled by upstream dams but about 20% of that “bathtub ring” can be attributed to the albedo effect.
In case you missed it: On Saturday 20 June 2020 the temperature hit 100.4 degrees F (38 degrees C) in the Siberian town of Verkhoyansk, north of the Arctic Circle! This is the town that also sets coldest temperature records.
Verkhoyansk holds the record for both the hottest and the coldest temperatures ever recorded above the Arctic circle, with 38.0 °C (100.4 °F) and – 67.8 °C (- 90.0 °F) respectively.
There’s a rule of thumb from the last century that says “Spring moves north 13 miles a day.” On average this means that if crocuses began blooming in Morgantown, West Virginia a week ago they ought to start blooming in Butler, PA today.
However this year’s spring is so early and so hot that I’m wondering if the rule is still true. The animated map below shows spring leaf out moving north from 1 January through 10 March 2020. Some days spring leaps many miles.
According to the USA National Phenology Network, spring is many weeks ahead of schedule, particularly in the eastern US. It’s “three to four weeks earlier than a long-term average (1981-2010) in some locations. Washington, DC and New York City are 24 days early, Nantucket is 30 days early.” Wow!
Leaf out in Pittsburgh began in early February, tulip leaves emerged in late February and I saw the first crocus bloom last week.
So what do you think? Is spring moving faster than it used to? Or just sooner?
Follow the signs of spring at the USA National Phenology Network and Journey North. Here are some cool maps that track what’s going on:
According to the USA National Phenology Network, Spring is three weeks ahead of schedule in the southeastern US:
Spring leaf out has arrived in the Southeast, over three weeks earlier than a long-term average (1981-2010) in some locations. Charlottesville, VA is 24 days early, Knoxville, TN is 20 days early, and Nashville, TN is 18 days early.
If you’re going to walk to the North Pole, February is the month to start. The sea ice is at maximum thickness, the weather is slightly less harsh, and you still have enough time to get there before the spring thaw. Or do you?
The North Pole is all water, covered by the Arctic Ocean which is covered by sea ice. Explorers can get there on foot in about 50 days — unassisted and without re-supplies — if the ice holds. However, climate change is warming the Arctic faster than anywhere else on Earth. The ice doesn’t hold anymore.
The last unsupported trek to the North Pole was completed six years ago.
In 2014, Eric Larsen and his partner, Ryan Waters, skied, walked, and swam 480 nautical miles from Cape Discovery on Canada’s Ellesmere Island to the North Pole, lugging all of their supplies with them on sleds.
Seven weeks later as they approached their goal the ice was breaking up.
When Larsen and Waters were just 33 feet from the North Pole, the ice under their feet was drifting away from the pole faster than they could walk. So they ran. On May 6, 2014, they reached the North Pole, becoming the 46th and 47th people to complete such a trek unsupported.
“It’s hard to describe, but the character and the nature of the sea ice is different. From a scientific perspective, the thickness of the ice is much less, so it’s much thinner, and the overall extent is less. So the icepack has shrunk,” he explains. “It definitely hit this real exponential change from 2010 to 2014.”
Amidst the raging bushfires in Australia there’s a bit of happy news. Wombats are unintentionally saving wildlife.
Wombats are nocturnal marsupials that live in burrows which they dig with their teeth and claws. Specially adapted for their underground life, the female’s pouch where she carries her young faces backward so the dirt doesn’t get into it.
Southern hairy-nosed wombats (Lasiorhinus latifrons) are the smallest of the three wombat species. At 30 inches long and weighing 42 to 71 pounds, their extensive tunnels have many entrances, long “hallways,” several large warrens, and smaller chambers. They are known to share their burrows with other wombats and are tolerant of visits by other species. Southern hairy-nosed wombats live in the fire zone.
Rescuers figured out the importance of wombat burrows when they found healthy, unscathed animals wandering in newly burned areas including small wallabies, echidnas, lizards, skinks and rabbits. As the fires approached, the fleeing animals dove into wombat burrows to shelter safely while the firestorm passed overhead.
Two species that may benefit from the wombat burrows are shown below.
The swamp wallaby (Wallabia bicolor) is common in the bushfire area, measuring 27-30 inches excluding its tail. Rock wallabies are even smaller.
Short-beaked echidnas (Tachyglossus aculeatus) are egg-laying mammals like the platypus that measure 12-18 inches long. They eat ants and termites.
Both studies correlated the annual mean summer temperature of the species’ breeding range and reached the same conclusion: As the climate heats up, birds are getting smaller.
We should expect this.
There’s a biological rule of thumb called Bergmann’s Rule which states that, within a species, populations living in colder climates have larger body size than those in warmer climates. Bergmann’s explanation is that large animals have a lower surface-area-to-volume ratio so they lose heat more slowly in cold climates while small animals have a higher surface-to-volume ratio and can cool off faster when it’s hot.
Song sparrows (Melospiza melodia) provide a good example of Bergmann’s rule because they range across North America from Alaska to Newfoundland and south to Mexico. I saw their variability up close in the Carnegie Museum of Natural History’s Section of Birds in December 2016. My photo below shows sparrows collected in Alaska in the top row, sparrows from Pennsylvania on the bottom.
Here’s a closeup placed side by side (below):
On the left, two song sparrows collected in Pennsylvania: Pittsburgh (leftmost) and Geneva Marsh.
On the right, song sparrows collected in Alaska’s Aleutian Islands at Unalaska (leftmost) and Sanak.
Alaskan song sparrows are so large that they have to be placed sideways in the tray!
Smaller size is normal where it’s warmer.
It isn’t bad news for birds and it tells us two additional things:
Birds’ bodies have been registering climate change long before we humans noticed or admitted it.
Now that climate change has really settled in there are loads of free fun winter activities that we can’t do in Pittsburgh. I was reminded of this when I heard that the Beaver County Snow Shovel Riding Championship was postponed last Saturday. Last year it was eventually canceled. As the Beaver County Times wrote last month:
The Beaver County Snow Shovel Riding Championship returns in 2020. That comes with the major assumption that sufficient snow rests on the 165-foot hill at Old Economy Park, just off Route 989 in Economy, on Jan. 11 or the makeup date of Jan. 18.
Last Saturday, 11 January 2020, was so hot that it broke a 130-year record. At Pittsburgh International Airport, nine miles from that Beaver County hillside, it was 71 degrees F. Of course there was no snow.
Other winter fun we’re missing includes building snowmen, making snow angels, and cross country skiing. These still might happen for a day or two if we get one big snowfall.
But some winter fun is just plain dangerous in today’s world. Ice fishermen used to count on our frozen lakes but these days the ice is missing or very thin. Unsafe!
To emphasize this dilemma, the Great Lakes were virtually ice free on January 12.
No winter fun.
(photos from Wikimedia Commons; map from U.S. National Ice Center; click on the captions to see the originals)