Category Archives: Climate Change

Won’t Live Where It’s Hot

Stresemann’s bush-crows, Soda Plains, Ethiopia (photo by Nik Borrow, Creative Commons license on Flickr)

Seven years ago I wrote about an endangered member of the crow family in Ethiopia whose range is small and shrinking. Similar in size and sociability to our Florida scrub-jay, Stresemann’s bush-crow (Zavattariornis stresemanni or Ethiopian bush-crow) lives in just 6,000 square miles of southern Ethiopia’s Borana rangelands in an area smaller than New Jersey.

Has the bird’s status changed in the last seven years? No, but we know more.

A 2012 study found that his range was limited by daily high temperature. In 2018 a team of scientists investigated further, taking temperatures throughout the region and comparing the bush-crow’s range to two other local species — white-crowned and superb starlings. Their report at the British Ornithological Union blog showed that Stresemann’s bush-crow has a narrow favorite temperature range and is heat intolerant.

The starlings don’t care how hot it gets but the bush-crow won’t live where the maximum daily temperature is over 30 degrees C (86 degrees F). (Graphs embedded below from

Figure 3 embedded from study in 2018 on Ethiopian bush-crow

This wouldn’t be a problem except that it’s getting hotter.

Find out more about the bush-crow’s dilemma at:

(photo of Stresemann’s bush-crow by Nik Borrow via Flickr Creative Commons license, Figure 3 embedded from High temperatures and hot birds; click on the captions to see the originals)

Tarballs in the Himalayas

Mt Everest, Himalayas (photo from Wikimedia Commons)

9 December 2020

Every November air pollution spikes in India as farmers in the Punjab burn their fields in preparation for the next crop. Because the practice causes terrible air pollution it was outlawed in 2015, but small farmers cannot afford to buy the machines needed to clear the fields so the practice continues year after year.

Burning stubble to clear the fields, Nov 2011, Punjab, India (photo from Wikimedia Commons)

When the stubble burns Delhi is smothered in dangerous air pollution. The smoke from thousands of fires swirls high in the atmosphere and can be seen from satellites.

Smoke from agricultural fires (red dots) swirls toward the Himalayas, Nov 2013, NASA MODIS satellite (photo from Wikimedia Commons)

Meanwhile glaciers in the Himalayas have been retreating for the past decade. Scientists wondered if atmospheric carbon air pollution, landing on the white ice, was a factor in their warming. A team led by Yuan Q placed air pollution monitors in remote locations on the northern side of the Himalayas. Their report, published by the American Chemical Society on 4 November 2020, found an amazing thing:

Using electron microscopy, the researchers unexpectedly found that about 28% of the thousands of particles in the air samples from the Himalayan research station were tarballs, and the percentage increased on days with elevated levels of pollution. Brown carbon ‘tarballs’ detected in Himalayan atmosphere , 4 Nov 2020

Microscopic tarballs form from brown carbon in the smoke of organic fires — in this case, stubble burning. They are so lightweight that they travel far, rising over the Himalayas to deposit on the other side. Their dark color absorbs sunlight and causes the glaciers to melt faster.

How smoke transforms to brown carbon tarballs in the Himalayas (CREDIT: ACS / Environmental Science & Technology Letters, graphic embedded from SciTechDaily news)

Stubble burning is a persistent annual problem in India as shown in the 2018 video from France 24 below.

Dec 2018: Crop burning crisis: India chokes as farmers set fields on fire, France 24 News

As India’s government provides community-shared machines for clearing stubble, the burning will come to an end. Will it be soon enough for the glaciers? Probably not.

Read more in this 4 Nov 2020 press release from Brown carbon ‘tarballs’ detected in Himalayan atmosphere

(photos from Wikimedia Commons, chart embedded from; click on the captions to see the originals)

The study is here: Yuan Q et al. Evidence for Large Amounts of Brown Carbonaceous Tarballs in the Himalayan Atmosphere. Environmental Science & Technology Letters. Published 4 November 2020.

No Need To Huddle

Ducks in a huddle (photo from Wikimedia Commons)

11 November 2020

As temperatures soared this week from 9 to 19 degrees above normal, I remembered the time when our furnace broke in late September 2009. We thought we could tough it out while we waited for the new furnace to arrive but it was cold! The temperature went down on 25 September 2009 and never came up again. Like ducklings, we huddled inside to stay warm.

This graph shows how much we needed the furnace in the fall of 2009. The higher the blue line, the more we needed heat. We didn’t need air conditioning (orange line) after 25 Sept 2009.

Not so this year! Every 10 days or so the temperature climbs so high that we’d benefit from air conditioning. Rather than flipping the thermostat from heat (blue line) to A/C (red line), I wear my summer clothes again. Climate change makes the temperature fluctuate widely.

For five days this month it was summertime even though the trees couldn’t provide much shade.

Schenley Park’s Serpentine Drive, 10 Nov 2020 (photo by Kate St. John)

Today the weather will turn cold. The furnace is ready. No need to huddle this year.

p.s. Read about our no-furnace adventure in this vintage article: Huddle!

(photos from Wikimedia Commons and by Kate St. John)

Hurricanes and Smoke

23 October 2020, 9:10a: Satellite shows Hurricane Epsilon near Bermuda and smoke from Colorado’s East Troublesome Wildfire crossing the Atlantic (image from GOES East, crop+description from Yale Climate Connections)

2020 has been a prolific year for heat, fires and hurricanes.

Last month was the hottest September on record, dangerous western wildfires have been burning since late July, and the Atlantic has had so many storms that the National Hurricane Center ran out of English alphabet letters and began naming storms using the Greek alphabet.

On Friday, 23 October 2020, Yale Climate Connections reported that a weather disturbance in the Caribbean is likely to become the sixth Greek alphabet storm, Zeta. That’s number 32. In the report they included an intriguing GOES EAST satellite image, above, with this explanation.

Smoke from Colorado’s second largest fire on record, the 170,000-acre East Troublesome Fire, was carried by the jet stream to the northeast of Hurricane Epsilon (upper right of image).

Yale Climate Connections: Disturbance in the western Caribbean likely to become Tropical Storm Zeta

As this moment Colorado’s East Troublesome Wildfire is burning through Rocky Mountain National Park and threatening Estes Park (click here for video). I’m not surprised the smoke showed up near a hurricane.

See more reports at Yale Climate Connections:

(image from GOES East cropped by Yale Climate Connections)

Sunrise and Heat

Sunrise in Pittsburgh, 18 October 2020 (photo by Kate St. John)

24 October 2020

Last week there was frost in the suburbs on 17 October. This week 23 October was unusually hot at 78-80 degrees F (26C) in Schenley Park. I had to wear summer clothes yesterday but will wear warm clothes tomorrow when it’s 38F. Join me at 8:30am at Bartlett Shelter in Schenley Park. Wear a mask.

Though it felt like July this week I found some beautiful autumn scenes in Pittsburgh.

Above, the sun rose red at 7:34am on 18 October for 11 hours of daylight. Today we’ll have only 10 hours 45 minutes of cloudy light.

Frick Park was golden yellow on 21 October.

Frick Park, 21 October 2020 (photo by Kate St. John)

The Panther Hollow Bridge cast a shadow on Schenley Park’s trees yesterday morning, 23 Oct.

Schenley Park, Panther Hollow Lake, 23 Oct 2020 (photo by Kate St. John)

p.s. You can tell it was a hot week in Schenley by the presence of algae on the water’s surface.

(photos by Kate St. John)

Arctic Sea Ice Is Connected To Everything Else

2020 Arctic Sea Ice Minimum (map from NOAA based on data from NSIDC)

Arctic sea ice melts in the summer reaching it’s lowest extent every year in September. On 21 September 2020, reported that ice coverage reached its minimum on 15 September, the second lowest extent in 40 years of tracking. (The lowest low was in 2012 only 8 years ago.)

We might think this lack of sea ice won’t affect us but in fact ice acts like a thermoregulator, reflecting the sun’s heat so that Earth’s climate stays relatively constant. As the ice disappears we’re subjected to heat waves, droughts, fires, and the cold Polar Vortex.

This 5-minute video from NASA Goddard shows how Arctic sea ice is connected to everything else.

(map from NOAA based on data from NSIDC)

Massive Die Off of Birds in New Mexico … why?

Dead orange-crowned warbler (photo from Wikimedia Commons used as an illustration, not taken in New Mexico)

18 September 2020

In late August reports started trickling in that high numbers of migratory birds were being found dead in New Mexico. The first report was at White Sands Missile Range on 20 August but as time passed the reports became more frequent, the locations increased, and so did the death toll. By now experts believe that hundreds of thousands of birds have died — perhaps millions — not only in New Mexico (red on map below) but in Colorado, Arizona and western Texas (orange highlight on map).

General area of U.S. where massive bird die off is occurring (map from Wikimedia Commons). New Mexico is red

Austin Fisher took a video of the carnage last Sunday, 13 September 2020 in Velarde, New Mexico.

Science Alert reports that only migratory birds are affected, not the local residents. Most of the dead birds are warblers, swallows and flycatchers and “the affected travelers seem to act strangely before their deaths, spending more time on the ground than perched in trees, and generally appearing dazed, sleepy, and lethargic.”

Dr. Andrew Farnsworth at Cornell Lab of Ornithology believes the smoke from the western wildfires is a big factor.

While birds migrate south through the Rockies this fall they must fly through the ubiquitous wildfire smoke blowing across the US from California, Oregon and Washington. Here’s what it looked like via satellite on August 20, the first day dead birds were reported in New Mexico. Notice that the smoke had reached New Mexico that day.

Satellite image of wildfire smoke across the U.S. west, 20 August 2020 (image from NASA)

Unfortunately birds’ respiratory systems are so different from ours and so efficient that they succumb quickly to bad air.

We turn oxygen into CO2 in one breath — in/out. Every exhalation releases the CO2/remains of the air we just breathed in.

When birds breathe, the air that enters their bodies stays inside for two breaths — in/out + in/out. During its 4-step journey, the air molecule travels through the lungs, two sets of air sacs and into the birds’ hollow bones where it waits for the next step. Click on the diagram below to watch the airflow inside a bird.

Birds’ respiratory system, screenshot from animation at Oxford Learning Link

Sadly, the western fires are damaging much more than we realize. UPDATE 23 Sept 2020: a recent study found that the birds died of hypothermia and starvation. See: Explaining the recent mass mortality of western birds.

Read more about the bird die off at Science Alert and the New York Times.

(images from Wikimedia Commons, NASA and a screenshot from Oxford Learning Link. Click on the captions to see the originals)

Smoke Gets In Our Eyes

Late afternoon sun looks pink in Pittsburgh, 14 Sept 2020 (photo by Jonathan Nadle)

16 September 2020

This week’s spooky sunsets and hazy skies in eastern North America are due to smoke from the massive wildfires in Washington, Oregon and California. The smoke is so intense that it’s dispersing across the continent and across the Atlantic, causing haze in Europe.

Near sunset on Monday 14 September the sun was a strange shade of pink in Pittsburgh, captured above in true color by Jonathan Nadle.

We can’t see the smoke coming but the satellites do, blowing eastward in two paths on Tuesday 15 September: one over the Northern Plains and Great Lakes, the other over Nebraska to Kentucky and Virginia.

It’s also blowing west over the Pacific, shown here on Friday 11 September.

The haze is inconvenient for us but truly hazardous on the West Coast. The dark brown colors on the map below are the worst air quality in the world. The air is so bad that people are leaving the area. I know of at least one person who’s fleeing from San Francisco to Pittsburgh.

screenshot of AirNow air quality map, 16 Sept 2020

By now the fires cover 4.5 million acres, an area so large that it’s hard to imagine. To help you visualize it The Guardian has created an interactive map comparing the fire acreage to well known cities and your own hometown — click here or on the tiny screenshot below. NOTE: The comparison below is for New York City. I compared the fire acreage to Pittsburgh and found it would run from approximately I-80 to the PA-West Virginia line!

Meanwhile the sunsets are still creepy.

Strange sun at sunset in Pittsburgh (filtered), 15 September 2020 (photo by Jonathan Nadle)

None of us are immune to this huge effect of climate change. Smoke gets in our eyes.

UPDATE: Janet Campagna, who lives in California, remarked that the days are much cooler because the sun can’t get through the smoke. This reminded me of the volcanic winter which results from smoke in the atmosphere after giant volcanic eruptions such as Krakatoa in 1883 and Mount Pinatubo in 1991.

(photos by Jonathan Nadle, screenshot of AirNow map from, screenshot of article from The Guardian)

Fall Migration is Earlier Due to Climate Change

American robin in flight (photo from Wikimedia Commons)

3 September 2020

Here’s something that’s counter-intuitive: As our climate changes we know that North America stays warmer in the fall yet songbirds that migrate at night — cuckoos, flycatchers, warblers, vireos, thrushes, orioles and sparrows — are leaving earlier on fall migration than they used to.

A study led by Kyle Horton published last December in Nature Climate Change found that in the past 24 years the peak of nocturnal migration is earlier in the spring — as expected because it’s warmer — but also earlier in the fall.

At Pittsburgh’s latitude (40oN) the spring peak is 1.4 days earlier, fall is 0.8 days earlier as shown in this graphic embedded from the BirdCast blog about the study: Phenology of nocturnal avian migration has shifted at the continental scale.

Predicted peak spring (a) and autumn (c) migration dates by year and latitude (figure embedded from BirdCast blog by Andrew Farnsworth)

You can see this play out in their video of annual migration phenology.

The video illustrates another amazing thing: The Central Flyway — the Great Plains and Mississippi Valley — is a much bigger songbird migration corridor than either coast.

p.s. Downtown Pittsburgh’s GPS location (rounded) is 40.44, -80.00

(photo from Wikimedia Commons, graphic and video embedded from BirdCast blog and Phenology of nocturnal avian migration has shifted at the continental scale; click on the captions to see the originals)

Disappearing into Thin Air

  • Lake Mead at Hoover Dam, 1998 (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.

U.S. Drought Monitor map as of 28 July 2020,

But drought is not the only factor. A study published last February found that 20% of the river flow has been lost to the albedo effect in a period of 20 years.

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.

The river is disappearing into thin air.

(photos from Wikimedia Commons. Colorado River watershed map from, drought map from