Hurricane Franklin is making landfall on the East Coast of Mexico Wednesday night/early Thursday morning (~midnight CDT Thursday) with maximum sustained winds of 85 mph with gusts likely over 100 mph. Besides damaging wind gusts, very heavy rain – up to a foot or more – will be possible in the mountainous terrain once the system moves inland and weakens during the day Thursday. Life threatening flash flooding and mudslides will be the greatest threats to any populated mountain areas (storm surge will be the hazard for coastal areas in the hurricane warning area tonight).
NOAA Raises North Atlantic Tropical Activity Forecast
The National Oceanographic and Atmospheric Administration raised its confidence today that the North Atlantic Basin would have an “very active” season. They called for 14-19 named storms, 5-9 hurricanes, 2-5 major hurricanes. A normal season averages 11 named storms, 6 hurricanes, 2 major hurricanes.
The reasoning for this activity forecast include 1) No El-Nino in the Eastern Pacific which would otherwise produce unfavorable vertical wind shear and cooler sea surface temperatures in the North Atlantic 2) Above normal sea surface temperatures across the Caribbean, Gulf of Mexico and Main Development Region (open tropical Atlantic) 3) The continuation of the Atlantic Multidecadal Oscillation favoring above normal oceanic heat content.
So far, we are at 6 named storms, 1 hurricane, 0 major hurricanes (assuming no surprise intensification of Franklin prior to landfall).
Hello Weather & Climate News readers! This post will be the first in what will be my ongoing education article series WxClimoEd. I hope to write educational posts on various topics related to weather and climate to help enhance your understanding of various phenomena and their impact on the environment, individuals and society. These posts will present key ideas and concepts and provide occasional linked sources to further, more detailed information.
Understanding Global Climate Change (Causes)
This article will deal with an introductory explanation of Global Climate Change as we currently understand it and the causes of it, specifically relating to human activity. Part 2 (in the next week) will discuss the known (and unknown) impacts on humanity and wildlife based on impacts on regional climates. Part 3 (in a couple weeks) will discuss mitigation efforts.
Natural Climate Variability vs. Recent Global Climate Change
Earth’s climate has been evolving since the planet was born 4.6 billion years ago. These changes in Earth’s atmosphere have been largely the result of things such as biological modification of the atmosphere, volcanic eruptions, changes in ocean currents, movement of continents over tens of millions of years, variations in Earth’s orbit and other various phenomena. The most recent history of climate has featured periods of glaciation over much of the landmasses known as the Ice Ages.
Earth’s global climate has been in a “interglacial” period with a climate which warmed enough to end major continental glaciation around 11,000 yrs ago.
However, what scientists have seen in the recent climate records is a rate of change -both the climate conditions themselves and the atmospheric gases which can change the climate – at a rate accelerated and in some cases unprecedented in previous times.
What scientists in the second half of the 20th century discovered is that for the first time in the history of human civilization we are acting as a force influencing the climate. Human-induced climate change is real.
This has been found after accounting for the natural variability in climate cycles and from our understanding of how carbon dioxide works in the atmosphere. This extremely rapid change in global temperatures, a top signal of climate change, has been driven by CO2 pollution, beginning after 1850 and the during the Second Industrial Revolution.
One of the first questions which many non-scientists have about global climate change is “Well hasn’t the climate always been changing?” The answer is yes, but with a caveat…it has NOT changed this rapidly in the history of humanity on Earth (Homo sapiens sapiens have been around ~200,000 yrs). Since Earth began the process out of the last glaciation 22,000 yrs ago, global temperatures have varied up to a 4 degrees C. But this process of variability has occurred over the course of centuries to a couple of millennia because of the long cycling of natural processes. Human activity in the form of burning fossil fuels since the latter 19th century has caused around 1 degree C of warming within a 100-150 yr period. This comic comparing the average temperature of Earth to the end of the Ice Age and achievements of human civilization across millennia strongly illustrate the climate stability we’ve come to flourish under. (zoom in at the top and scroll down…it’s long, but worth the read and look!). Humans have essentially acted as a continuously spewing ‘volcano’ of carbon products. And as a result, we have compressed warming which would take nature nearly a millennia to do in recent geologic time and accomplished it within a century.
We are transforming our world before our eyes.
2. How does the greenhouse effect work?
The greenhouse effect is a simple concept, but one with major implications for us all in this major environmental issue. In Earth’s atmosphere exists gases which are chemically capable of “trapping” heat in the lower atmosphere, heating the surface. The three most significant “greenhouse gases” are carbon dioxide, water vapor, and methane. These gases in higher concentrations are most effective in reflecting infrared (heat) radiation originally emitted by Earth’s surface back to the surface as opposed to allowing it to be lost to space. If it wasn’t for this greenhouse effect, Earth would be literally completely glaciated over and very cold.
Methane is very potent, but short-lived without constant replacement as direct sunlight breaks the molecules apart. Water vapor varies seasonally with some balance because of the water cycle. Therefore carbon dioxide or CO2 ends up being the most important changing variable for warming/cooling the climate. Such changes, along with other variable cycles, have influenced previous periods of ice ages. But human “eruption” of CO2 since the 2nd half of the 19th century has led to clear changes in Earth’s atmosphere and climate.
This YouTube video shows 131 yrs of global warming (1880-2011). The “anomalous temperature” is relative to the average planetary temperature of 1880-1910. The average temperature of Earth has continued to warm above this average to record levels since 2011. The planet is known to have warmed by ~1 degree C (nearly 2 F) since the late 19th century. The most dramatic warming (as can be seen in the video) began to ramp up significantly since 1980. Depending on the scenario, human-induced warming of Earth may reach 1.5-2 degrees C (2.7-3.6 F) above pre-industrial levels by 2050 and (depending on human efforts to decrease CO2 pollution) the warming may hit 2-4+ degrees C (3.6-7.2+ F) by 2100.
3. The importance the rate of warming
Such rapid rates of warming are what alarms climatologists and those who understand the importance of climate stability for life and society on Earth. Remember the last time you saw a wholly mammoth, saber-toothed cat, wholly rhino, or an indigenous North American horse? Never because they all went extinct from the “rapid” climate change of the final end of the ice age glaciation 11,000 yrs ago. What’s “rapid”? Temperatures warmed more than 2.5 degrees C over the course of 1500 years. We may accomplish that in 150-200 yrs! Incredible. But yet the “rapid” natural changes were not non-consequential. Many more species than listed which couldn’t adapt died out over hundreds to a couple thousand years. And minor variations in global climate by 0.5 degrees C or less – or even significant regional variations which barely showed up on the global signature – have led to major losses in agriculture and economics producing stresses on some nations (poverty, famines, wars) and in some cases, isolated civilizations simply died out. Having such rapid, unprecedented warming is a cause for concern because too many species (and many socio-economic or geographically vulnerable peoples) may face significant harm in the face of an inability to adapt to transforming climate regimes.
In Part 2, later this week, I’ll discuss the effect climate change has on regional climates and likely impacts being faced by humans and wildlife as the climate continues to heat up extremely quickly.
It was VERY smoky in the Northwest Wednesday unfortunately because of major fires in the Interior US and Canada.
BELOW were the highs Wednesday for select cities. Southwest WA and Western OR are being particularly hit hard by this heat wave. Interior Western WA and Puget Sound were actually sparred some of the worst of the heat today by the smoke; it was thick enough to act as a cloud to dampen the radiation and limit warming in places such as Seattle. It remains to be seen if that will be the case Thursday. If not, the hottest day if the heat may very well be Thursday for Western WA (and about the same for Western OR). This, along with an Air Quality Alert in effect for much of Western WA/OR means those in the area will need to not only be careful with strenuous activity to avoid heat-related illnesses, but also avoid breathing problems, if sensitive to such smoke particulates.
(record highs in red)
Seattle (National Weather Service Office): 88
Seattle (International Airport): 91 – Old Record 89 (2009). Special Note: Seattle also shattered its daily record for warmest minimum temperature with a morning low of 69 (old record was 61 set back in 2015) and it ranks as the 2nd warmest daily minimum temperature on record.
Hoquiam: 89 – Old Record 81 (1993)
Quillayute (North WA Coast): 98 – Old Record 89 (1993). Special Note: This was likely caused by easterly downslope winds; easterly surface winds flowing along the higher hilly terrain descends down the slopes resulting in “adiabatic heating” (compression heating from increasing pressure on the air molecules as the flow drops in elevation). This hot air blows into town and shoots the temperature up fast. This process occurs throughout the region and is the reason why it is typically a “dry heat” in Western WA/OR during heat waves. The heated air becomes dry, with little moisture added to it.
Astoria: 93 – Old Record 88 (1939)
Portland (International Airport): 103 – Old Record 96 (1986)
Troutdale (East Portland Metro): 105 – Old Record 99 (1995)
Hillsboro: 105 – Old Record 99 (1939)
Salem: 107 – Old Record 102 (1939)
Eugene: 102 – Old Record 99 (1939)
Medford: 112 – Old Record 105 (1993)
Klamath Falls: 99 – Old Record 94 (1977)
As you see, for Oregon, there was a major theme in the records for Wednesday’s climate stations. It was the hottest day many of these locations had seen on this date since 1939.
Please be safe if you live in this region the next couple of days. Drink PLENTY of water, take breaks from the heat as necessary, use fans if you don’t have air conditioning (common problem in this region, I lived there without air conditioning and the summers statistically are generally getting warmer because of anthropogenic climate change…), and again, like me, I have asthma; if you don’t need to do anything strenuous outside DON’T! Just drive instead of walk or just stay inside, cool and relax. The slightly cooler weather (still above normal, however) starts Friday.
The past couple of weeks, the Eastern Pacific Basin has been quite active with multiple active tropical cyclones churning, dying and new ones forming. All while the North Atlantic Basin has been largely silent. We’ll get into the pattern set up for tropical activity between the two basins in the coming few weeks in a moment. But first, let’s discuss two interest systems in process in the EPac – Hilary and Irwin.
(Intensities are as of 4 pm CDT Thurs)
Hurricane Hilary is currently a Category 1 with max winds of 75 mph moving to the west-northwest. Meanwhile, ~480 nautical miles southwest of Hilary is Tropical Storm Irwin. It has max winds of 60 mph and drifting westward. Neither system is a threat to populated land masses and both are quickly heading for cooler waters north of the subtropical Pacific, where much drier air also exists in the mid-levels of the atmosphere. Both will lead to rapid deterioration of the cyclones this weekend.
Later Sunday and into Monday, an amazing phenomenon is expected to occur. Because of the very close proximity of Hilary and Irwin – only several hundred miles apart – the two cyclones are expected to undergo a Fujiwhara Interaction. This describes when two vortices in close proximity begin to rotate around a common center or one around another if one is more dominant. It is named after the Japanese meteorologist Sakuhei Fujiwhara who first described the interaction scientifically in a 1921 paper.
It does not happen very often, but it is typically more common in the Western Pacific basin where a very large surface area of favorable tropical development and maintenance exists and many cyclones can develop simultaneously and sometimes in close proximity.
Numerical models have shown the possible interaction for days.
The slideshow above displays the Hurricane Weather Research & Forecasting Model forecast initialized at 11 pm PDT Wednesday with the forecast valid 5 pm PDT Sunday – 11 am PDT Monday. This model is “nested” on Hilary to show its evolution (the colors are surface temperatures in degrees C and wind barbs are in knots). However, you can see Irwin orbiting around it on its south and east sides Sunday evening – Monday morning. Irwin will likely weaken and die (along with Hilary, not long after), or will become absorbed by Hilary.
Nature never ceases to amazes in what it can do with the laws of physics!