Hudson Valley Climate Change

Climate Change in The Hudson Hills and Highlands: What Can we Expect?

World leaders recently gathered in Copenhagen to debate how humankind should respond to a warming planet and changing climate. Optimists concluded that progress was made in Copenhagen, but from my perspective the results were more hot air than political resolve.  This lack of commitment tells me that collectively people don’t fully understand the climate change issue: what we know and how we know it; what is likely to happen and when; and how will a warming planet affect us locally in our daily lives.  Luckily, there is much information available online.  As a starting point, I recommend the Intergovernmental Panel on Climate Change, and the National Council for Science and the  Environment’s websites Climate Solutions and the Encyclopedia of Earth.

In the last century, the Earth’s average surface temperature increased by over 1^oF. The warming has been greater at the poles, already significantly reducing polar ice and changing weather patterns and sea level heights worldwide. The Earth is now warmer than it has been in 650,000 years – and is expected to climb another three to ten degrees this century!

Scientists tell us that a rising temperature of just a few degrees, surprisingly will cause a cascade of  detrimental climatic changes (e.g. in precipitation patterns causing both droughts and floods, and in sea level heights) and biological changes (e.g. in geographic ranges of wildlife and rates of species survival). In the last decade, a broad scientific consensus has emerged that global warming and climate change are due to increased levels of greenhouse gases in the atmosphere. While volcanoes and other natural events release greenhouse gases, it is the human-driven emissions of carbon dioxide over the last 150 years from burning fossil fuels for energy, as well as released gases from  deforestation and our agricultural practices, that are responsible for a warming Earth.

Global warming and climate change are global and local issues. Globally, never before has a pollutant released anywhere had a worldwide impact. The flip side is, regardless of where greenhouse gases are reduced, the world benefits. However, despite the global nature of the cause of global warming, the specific consequences to people (e.g. losses or gains of arable land and more or less flooding) will vary greatly from place to place. Adjusting to these shifting geographies will be a key challenge for people everywhere.

 Hudson Valley’s Future Climate

Will Hudson Valley winter scenes like this one be in our future? Maybe not, as climate change already is evident in New York’s Hudson Valley. A Columbia University study in 2001 found that over the past 100 years, temperature in the New York Metropolitan Region warmed nearly 2^oF, double the global average, and precipitation increased 2%. The Union of Concerned Scientists reports that since 1970, the Northeast United States has been warming at a rate of nearly 0.5°F per decade. Winter temperatures have risen even faster, at a rate of 1.3°F per decade. This warming has been correlated with many other climate-related changes in the Northeast, including: 1) more frequent days with temperatures above 90°F; 2) a longer growing season; 3) less winter precipitation falling as snow and more as rain; 4) earlier spring snowmelt resulting in earlier peak river flows; 5) rising sea levels; and 6) increasing storms with flooding.

Naturalists in the Hudson Valley also have made observations consistent with climate change predictions. Thirty years ago, for example, the Carolina Wren was rarely seen at Teatown, now this once southern bird species is common. Some botanists suggest that vines and poison ivy are increasing dramatically along our roadways because of their special ability to utilize rising levels of carbon dioxide for growth. One recent study estimated that 30% of species in the United States have responded to changing climates by shifting home ranges or adjusting their timing of seasonal events. Biologists fear that because species have different abilities to respond to climate change our natural communities are under considerable flux. Within the context of an already stressed environment, climate change might lead to damaged ecosystems, many species extinctions, and loss of ecological services.

While it is agreed that our weather is changing, do we know what our future Hudson Valley climate will be, say in 2100? The answer is “somewhat,” but the ultimate outcome depends on our current and near future actions. There is a lag between our actions and the consequences to global warming. Our past greenhouse gas emissions, for example, have already determined our fate for the next 20-30 years, but the actions the world takes starting now will set the climate in the Hudson Valley in 2100. Also, just how well Valley residents are able to cope with their climate in 2100 will depend on how wise our preparations are over the course of this century. A storm is coming, preparedness is key.

Last year, The Nature Conservancy’s New York Eastern Chapter in collaboration with a diverse group of 160 stakeholders initiated “Rising Waters,” a project to help Hudson Valley communities prepare for climate change. Assuming mid-level amounts of emission reductions, the project provided a hint of what our Hudson Valley climate might look like in 2030 and 2100.  The project also presented four scenarios that describe different outcomes based on differing  types of  preparedness for the Hudson River Estuary Watershed from 2010 to 2030. These scenarios help us imagine the future — hopefully to take action today. One variable among the scenarios of special relevance to environmentalists is how much will we try to control nature versus working with nature. For example, will we try to control flooding along rivers with engineering solutions or “give rivers room” by increasing the size of regulated flood plains.

Predicted Hudson Valley Climate, 2030 and 2100. Baseline for all variables is the average of 1961-1990 values, except for temperature, sea level, and snow, where the baseline is the average from 1970-1999  (adapted from the Rising Waters Project, Nature Conservancy, Mt. Kisco, NY).

Climate Variable	2030	2100
Average Annual Temperate	+ 2.20°F	+6.2°F
Average Winter Temperature	+ 3.3°F	+ 7.8°F
Sea Level Rise	+ 2.8 inches	+ 16.5 inches or more
Precipitation	+ 0.6%  More intense storms	+ 8% More intense storms
Snow	More rain and less snow	Even more rain and less snow
Heat Waves	22 days per year over 90°F and 3 days over 100°F	54 days per year over 90°F     and 16 days over 100°F
Timing of Seasons	Growing season 5 days longer	Growing season 35 days longer

 

 Responding Locally to a Warming World

Our local responses to global warming in the Hudson Hills and Highlands will likely fall into two broad areas: 1) reducing greenhouse gas emissions; and 2) preparing for the human consequences from climate change. Lowering our share of the world’s greenhouse gases will primarily come through the same actions that ought to take place everywhere: improved energy production and conservation; more efficient cars and transportation systems; more efficient industrial and agricultural practices; more mindful consumer purchasing practices; and new land use and smart growth policies.

Based on current climate predictions, preparations for climate change in our Hudson Valley region likely will focus on the expected extreme weather and the inevitable detrimental affects to human health. We will need to improve our adaptations to flooding and heat waves. Physicians will need to be alert to new patterns of disease. Sea level rises are especially problematic for Manhattan and along the Hudson River, because the most recent data suggest that our current estimates for rising seas, which already are bad, might be understated. Climatologists now believe that the Northeast United States will suffer some of the greatest sea level rises in the world! Destruction of private property from storm surges, frequently flooded roads and rail lines, and even seeing southern Manhattan underwater are possibilities. These consequences, of course, will bring huge financial implications with them to the Hudson Valley and New York. We need to be preparing now for these events through improved regional planning, changes to infrastructure and climate-realistic policies.  Unfortunately, in the midst of an economic crisis, local preparations largely have stalled.   

 Conserving Nature Will Be Key to our Children’s Survival

From an ecological perspective, a necessary third response to global warming in the Hudson Valley (and everywhere) is needed: help nature prepare for the consequences of climate change. While it is understandable that civic leaders focus first on human interests  (e.g. flooding, food production and transportation), ultimately, if our natural foundation is broken our human communities will fail. Nature is the ultimate cornerstone of our economic prosperity and well-being. Healthy levels of biodiversity and functioning ecosystems are necessary to build a sustainable world for our children and all future generations. Therefore, part of the solution to climate change is to help species survive across broad regions – to keep landscapes living and ecological services in tact.

Four actions to help nature survive climate change in the Hudson Valley are: 1) reduce other environmental stressors, such as habitat lost, invasive species, and pollution; 2) work with nature whenever possible, rather than trying to control nature; 3) conserve more land, especially around and between already protected parcels; and 4) make private land more nature-friendly.  Conserving land,  building corridors between parks, and adding more nature-friendly private land will make it easier for animals and plants to respond to climate change when they move north and need to adjust to new ecological communities. Scientist would say, “we are adding resilience to the system.” Conserving land will be especially important because it both helps nature survive and it helps reduce greenhouse gases. For example, 16% of our country’s carbon emissions are currently offset by open space. All of us can contribute to these four actions. Together we can make a difference!

Fred

Note:  This article first appeared  in Teatown Lake Reservation’s Winter 2010 Trails magazine.