Warmest Decade on Record

Cartoon by Pat Bagley of the Salt Lake Tribune

Occasionally I see arguments that climate change has slowed down or reversed course. Such arguments usually cite 1998 as the warmest year on record and insist that the (slightly) cooler years since then mean that we have nothing to worry about. However, if you look at a longer trend, the present decade looks less like a reprieve than a plateau on a continuing trend. The years 2000-2009 are the warmest decade on record, and 2009 is on track to be the fifth-warmest year.

While 1998 is still considered the warmest year on record, researchers say that preliminary data shows 2009 will likely be the fifth warmest. The analysis also shows that while the US and Canada experienced cooler than average temperature this year, temperatures in Southeast Asia and Africa could be the warmest yet.

Warmer temperature exacerbated drought conditions across the world. According to WMO, China experienced its worst drought in five decades. Drought in East Africa killed tens of thousands of livestock, while a poor monsoon season hit India's agriculture hard. A crippling drought in Australia also continued unabated this year.

Temperature data is collected from climate and weather stations around the world, ships and buoys on the sea, and satellites.

The record achieved is, of course, the modern record as established by instrumental data since the middle of the nineteenth century. Unfortunately we do not have instrumental records going beyond that. However, analysis of physical records such as tree rings and ice cores, both of which are sensitive to changes in temperature, suggests that current temperatures are higher than they have been in the past millennium. Atmospheric carbon levels are also at all-time highs, according to physical evidence.

A second point worth noting in this recent report is that lower temperature or cooler weather in one region or even continent is not a sign that the global warming trend has stopped. The study of climate change is based on long-term averages of much larger areas.

IPCC graph of the average global temperature for the past 140 years and Northern Hemisphere temperature for the past 1000 years

Copenhagen and Wildlife

BirdLife is requesting five things from the negotiators at the climate conference in Copenhagen.

1. Cut global emissions by the amount needed to limit global average temperature rises to less than 2°C above pre-industrial levels. Developed countries should take the lead in cutting emissions, but rapidly industrialising developing nations must act too. Global emissions must peak and decline well before 2020, and go to 80% below 1990 levels by 2050. Industrialised countries must take on targets of 40% reductions below 1990 levels by 2020.

2. Recognise the vital importance of safeguarding biodiversity, ecosystems and the essential services they provide in climate change mitigation, in particular, reducing emissions from deforestation and degradation (REDD). Tropical deforestation accounts for 15-20% of all human-induced emissions, and must be reduced to zero by 2020. REDD should prioritise conservation of natural tropical forests because they are the most carbon dense, and must exclude conversion of natural forests to industrial forests or plantations. REDD must include provisions which ensure conservation of biodiversity because it is the plants and animals in natural forests that help create their carbon density. REDD must respect, support and promote the rights of local and indigenous peoples.

3. Recognise the vital importance of safeguarding biodiversity, ecosystems and the essential services they provide in climate change adaptation. Healthy bio-diverse environments play a vital role in maintaining and increasing resilience to climate change. Copenhagen outcomes should encompass taking an ecosystem approach to all adaptation, should refer to the direct use of ecosystems as part of a strategy to help people adapt to the adverse effects of climate change, and should recognise vulnerable ecosystems as a priority concern.

4. Provide funding for developing countries to reduce emissions from deforestation, enable adaptation to climate change, and support low-carbon development. At least $200 billion will be needed annually by 2020, including $35 billion for REDD, and $100 billion to enable developing countries to adapt to the inevitable impacts of climate change.

5. Ensure that when developed countries account for their land-use sectors they account fully for carbon emissions to, and removals from, the atmosphere. Current rules enable countries to hide emissions whilst claiming credit for carbon storage, and the rules proposed in Copenhagen are shaping up to be even worse than the old ones.

The link provides a bit more about their reasoning. I think this is a reasonable list, though I doubt this conference will meet the first goal based on reports in the last few weeks. I hope that the other items will be included in some form. Natural habitats are important carbon sinks, and land use changes (especially moving from natural to developed landscapes) are a major source of emissions. That applies as much to landscape development for "green" projects – from LEED-certified buildings to renewable energy sites – as it does to other types of development.

EPA Recognizes Carbon Emissions as a Threat

Today the EPA declared carbon emissions to be a threat to human health and welfare, which will obligate the agency to regulate carbon dioxide as a pollutant.

Jackson said that she did not know when the EPA would reveal detailed plans for cutting greenhouse-gas emissions, or if the agency would wait to see if the U.S. Senate passes climate legislation early next year. Jackson said that legislation was still the best way to tackle the problem -- but said she was not trying to prod Congress with Monday's finding.

Instead, Jackson said, the administration was bound to follow the U.S. Supreme Court's order in 2007 to determine if these emissions endanger public health. ...

Businesses argue that such a finding would mean even emitters as small as a mom-and-pop grocery store would be forced to comply with onerous greenhouse gas regulations. The administration has crafted rules that would exempt facilities that emit less than 25,000 tons of carbon dioxide or its equivalent annually. But it remains unclear whether that exemption would hold up in court.

I have trouble believing that the timing of the announcement is an accident, as it coincides with the opening of the major climate conference in Copenhagen. It demonstrates some seriousness on the part of the Obama administration as they meet with other world leaders to negotiate a new treaty. Whether or not Jackson intends to put pressure on Congress to pass a cap and trade bill, today's declaration ought to make such a bill more attractive to both supporters and opponents, not just as a way to start regulations but also as a way of influencing their impact.

Past EPA regulations have met with similar wailing on the part of entrenched interests, but ended up costing a lot less than advertised.

Climate Conference at Copenhagen

Average Temperature of the Northern Hemisphere based on published research. The black line at the right is instrumental data recorded since 1856; follow the link to see the other sources. Figure created by Robert A. Rohde and distributed under a Creative Commons License.

Today representatives from numerous countries and organizations are starting a conference in Copenhagen to discuss the changing climate. The meeting was intended to produce a new international treaty to replace the Kyoto Protocols from 1998. Whether such a treaty will be signed this month remains to be seen; some news reports have indicated that negotiations might continue into early next year.

Even if a treaty is signed, it is likely to result in lower emissions reductions than needed. The scientific consensus appears to be that the highest atmospheric carbon levels that the climate can tolerate without triggering catastrophic change is about 350 parts per million. Even that level would trigger some rather uncomfortable effects. Since we are already above that level, emissions need to be cut deeply rather than just stabilized. Most accounts I have read suggest cutting global carbon emissions 80% by 2050, with a somewhat lesser goal by 2020. In the past few months, Obama has suggested cutting U.S. emissions 4% by 2020 (with more cuts later), while European leaders offer a 20% cut (3o% if the U.S. agrees to do it to) by 2020.

To some extent, making a smaller cut now could start the ball rolling towards deeper cuts later. However, this present an element of risk. To date, temperature changes have tended to match the worst case forecasts presented by the IPCC. If that trend continues, even faster and deeper cuts may be necessary to forestall catastrophic changes. Our governments really ought to make a serious start now.

Snow

As I mentioned in my post this morning, yesterday was our first snowstorm of the season. We did not get very much, just enough to coat the ground with a thin crust of snow and ice. Here are a few photos of snow-covered plants in the garden.

Since the snow was mixed with freezing rain and sleet, some of the precipitation froze clear, allowing the purple of the leaves to show through the accumulated snow.