In Gore’s commencement speech at Hamilton College:
“Similarly today, we have a debate in our nation about whether our climate crisis is real,” Gore said. “Mother Nature has weighed in if you will think about the events in the last 12 months.”
He said in the last year, Pakistan and Australia have seen massive flooding, Texas and Russia have endured wide-scale drought and fires, and the Mississippi River is facing the largest floods in recorded history.
“These events have been just in the past 12 months, and the scientists are now in a shift in their rhetoric saying that if you ask the question, ‘Would these events happened in the absence of man-made global warming?’, the answer is almost certainly no.”
BBC on the Pakistan floods in 2010 — global warming or bad river management?
Climate change may not be the only cause of Pakistan’s woes. There is also a sense that the current floods have been exacerbated by the way the Indus has been managed.
In the UK, flood risk is reduced by building levees (embankments) along vulnerable part of rivers. These barriers prevent them from bursting their banks in extreme floods. It is a system that has served well for generations.
But Pakistan’s rivers are different.
UK rivers carry very little sand and mud. In contrast, the Indus is choked with sediment eroding off the Himalayas. Building levees causes the river channel to silt up.
This has the unexpected effect of making Pakistan’s rivers prone to even bigger floods when the levees eventually break.
“What we’ve done is apply a system from the West that just doesn’t work [in South Asia],” said Professor Sinha.
What’s the primary cause of the Australia flooding, which now covers an area the size of France and Germany combined and has caused an estimated $6 billion in economic damage? The La Niña ocean-atmosphere phenomenon in the Pacific.
[. . .]
Both El Niño and La Niña are naturally occurring events that represent extremes in weather and occasionally wreak havoc on human population centers. Australia and Indonesia often see drought during El Niño, while La Niña typically causes higher rainfall there.
“In a general climatological sense, La Niña is always associated with very active rainfall conditions,” Dr. Kolli, chief of the World Climate Applications and Services Division, says in a telephone interview from Geneva. “But it won’t tell you exactly at what time of the season there will be very heavy rainfall. It helps people at being prepared, but you cannot use that information to take specific action in terms of a specific flood event.”
Moreover, he says, La Niña is only one of the many contributors to the heavy rain now hitting eastern Australia.
“The severity of the impact can be different,” he says. “La Niña is not the only factor that causes the active rainfall conditions. We need to investigate with more detailed data on exactly what happened [in Australia].”
Physorg.com on the Texas wildfires — global warming or too much rain last year?
Dylan Schwilk, an assistant professor in the Department of Biological Sciences, researches plants and fire. He’s studied the effects of wildfires in places such as the California, South Africa, Australia and Texas.
The current fire problem in West Texas is being fed by dormant, warm-season perennial grasses throughout the high and rolling plains area he said. Last year’s El Niño event helped these grasses grow thick. After going dormant for the winter, and because of this year’s La Niña drought, it’s left plentiful fuel lying on the ground.
“Here in West Texas, we get these powerful, low-humidity winds,” he said. “It’s amazing what fire will carry through out here. Even in heavily grazed areas, the winds lay fires flat. It’s very likely the relatively good rain we received last year contributed to higher fuel loads.”
Though recent fires make the landscape look devastated, almost all parts of the plants will survive the fires because grasses are still dormant and have very little living tissue above ground at this time of year, Schwilk said.
Most native woody plants, such as oaks, mesquite and other shrubs, will build new shoots from below-ground tissues even if partially or wholly burned. Also, some oaks have protective bark that shield the plant from fire.
Since the late-Miocene Period about 8 million years ago, fires have actually helped the spread of warm-season grasslands in Texas, such as those in the Southern High Plains. The grassfires burn hot, move very quickly, but they mainly burn upward. Grasses resprout because temperatures at the soil level don’t get hot enough to kill the root system.
The AFP on Russia — global warming or stupid Soviets?
This month, forest fires are already raging in Siberia, the Urals, and far eastern Russia, while peat bogs are smouldering in central Russia, Yaroshenko said.
“In a week’s time, the situation risks escalating in a catastrophic manner… and we will have a repeat of last year’s situation,” he said.
The noxious smoke could veil Moscow a month earlier than last year, in July, he warned.
Peat bogs were drained in Soviet times to extract fuel for experimental power stations. Once alight, the fires are particularly hard to put out because they continue to burn underground.
Peat fires are easier to extinguish at an early stage, but the emergency situations ministry “prefers to hide rather than react to warnings,” said Grigory Kuksin, head of Greenpeace Russia’s firefighting programme.
And finally, ABC News on the Mississippi floods — global warming or bad river management and incorrect estimates from the Army Corps of Engineers?
“If the rainfall increased in a forest the forest is going to suck up 90 percent of that rainfall. But if it happens in a urban area the pavement and roofs aren’t going to suck up anything,” Bosworth told ABC News.
The affect is multiplied on the mighty Mississippi because rivers in 31 states drain into it or its tributaries.
“The rivers need some room and we are getting that message explained very clearly to us year after year. It’s time we smelled the coffee,” said Robert Criss, professor of earth and planetary sciences at Washington University in St. Louis. “There is a lot of evidence that floods are not only getting deeper and more severe, but also more frequent.”
Criss attributes the rise in devastating floods to the continued constriction of the waterways and increased building in vulnerable areas. He says that as levees continue to be built higher it creates water that has enough power to tear through a landscape like a tsunami if the levee is breached, destroying everything in its path.
“What we need instead is a more thoughtful system where we have gates within levees and when we require flood water storage these gates are opened,” said Criss. “This will save levees, save farms and rejuvenate soil.”
Criss says that when water is released at a massive rate like in Cairo, Ill., when the Corps blasted the levees to flood farm land and save homes, it is a destructive process and the land is often not salvageable.
Both Criss and Bosworth agree that part of the problem is inaccurate assessments by the Corps.
Here some advice for the graduates of 2011: Don’t believe what comes out of Al Gore’s mouth.