The reliance on freshwater released by mountain glaciers and ice caps demands that the effects of climate change on these thermally-sensitive systems are evaluated thoroughly. Coupling climate variability to processes of mass and energy exchange at the glacier scale is challenged, however, by a lack of climate data at an appropriately fine spatial resolution. The thesis addresses this challenge through attempting to reconcile this scale mismatch: glacier boundary-layer observations of meteorology and ablation at Vestari Hagafellsjökull, Iceland, and Storglaciären, Sweden, are related to synoptic-scale meteorological variability recorded in gridded, reanalysis data. Specific attention is directed toward synoptic controls on: i) near-surface air temperature lapse rates; ii) stationarity of temperature-index melt model parameters; and iii) glacier-surface ablation. A synoptic weather-typing procedure, which groups days of similar reanalysis meteorology into weather categories , forms the basis of the analytical approach adopted to achieve these aims. Lapse rates at Vestari Hagafellsjökull were found to be shallowest during weather categories characterised by warm, cloud-free weather that encouraged katabatic drainage; steep lapse rates were encountered in weather categories associated with strong synoptic winds. Quantitatively, 26% to 38% of the daily lapse-rate variability could be explained by weather-category and regression-based models utilizing the reanalysis data: a level of skill sufficient to effect appreciable improvements in the accuracy of air temperatures extrapolated vertically over Vestari Hagafellsjökull. Weather categories also highlighted the dynamic nature of the temperature-ablation relationship. Notably, the sensitivity of ablation to changes in air temperature was observed to be non-stationary between weather categories, highlighting vulnerabilities of temperature-index models. An innovative solution to this limitation is suggested: the relationship between temperature and ablation can be varied as a function of weather-category membership. This flexibility leads to an overall improvement in the simulation of daily ablation compared to traditional temperature-index formulations (up to a 14% improvement in the amount of variance explained), without the need for additional meteorological data recorded in-situ. It is concluded that weather categories are highly appropriate for evaluating synoptic controls on glacier meteorology and surface energetics; significant improvements in the parameterization of boundary-layer meteorology and ablation rates are realised through their application.

Basal Temperature of Snow (BTS) measurements were used as the primary inputs to a high resolution (30 x 30 m grid cells) empirical-statistical regional permafrost probability model for the southern and central Yukon, and northernmost British Columbia (59° - 65°N). Data from seven individual study areas distributed across the region were combined using a blended distance decay technique, with an eighth area used for validation. The model predictions are reasonably consistent with previous permafrost maps for the area with some notable differences and a much higher level of detail. The modelling gives an overall permafrost probability of 52%. North of 62°N, permafrost becomes more extensive in the lowland areas whereas farther south permafrost is typically common only above treeline. Significant differences exist between the mountain environments of the Yukon and the Swiss Alps where the BTS method originated and as a result different modelling approaches had to be developed. This work therefore: (1) develops additional explanatory variables for permafrost probability modelling, the most notable of which is equivalent elevation, (2) confirms the use of ground truthing as a requirement for empirical-statistical modelling in the Yukon and (3) uses a combination of models for the region in order to spatially predict between study areas. The results of this thesis will be of use to linear infrastructure route-planning, geohazard assessment and climate change adaptation strategies. Future work employing the model will allow the effects of scenario-based climate warming to be examined.

Basal Temperature of Snow (BTS) measurements were used as the primary inputs to a high resolution (30 x 30 m grid cells) empirical-statistical regional permafrost probability model for the southern and central Yukon, and northernmost British Columbia (59° - 65°N). Data from seven individual study areas distributed across the region were combined using a blended distance decay technique, with an eighth area used for validation. The model predictions are reasonably consistent with previous permafrost maps for the area with some notable differences and a much higher level of detail. The modelling gives an overall permafrost probability of 52%. North of 62°N, permafrost becomes more extensive in the lowland areas whereas farther south permafrost is typically common only above treeline. Significant differences exist between the mountain environments of the Yukon and the Swiss Alps where the BTS method originated and as a result different modelling approaches had to be developed. This work therefore: (1) develops additional explanatory variables for permafrost probability modelling, the most notable of which is equivalent elevation, (2) confirms the use of ground truthing as a requirement for empirical-statistical modelling in the Yukon and (3) uses a combination of models for the region in order to spatially predict between study areas. The results of this thesis will be of use to linear infrastructure route-planning, geohazard assessment and climate change adaptation strategies. Future work employing the model will allow the effects of scenario-based climate warming to be examined.

Basal Temperature of Snow (BTS) measurements were used as the primary inputs to a high resolution (30 x 30 m grid cells) empirical-statistical regional permafrost probability model for the southern and central Yukon, and northernmost British Columbia (59° - 65°N). Data from seven individual study areas distributed across the region were combined using a blended distance decay technique, with an eighth area used for validation. The model predictions are reasonably consistent with previous permafrost maps for the area with some notable differences and a much higher level of detail. The modelling gives an overall permafrost probability of 52%. North of 62°N, permafrost becomes more extensive in the lowland areas whereas farther south permafrost is typically common only above treeline. Significant differences exist between the mountain environments of the Yukon and the Swiss Alps where the BTS method originated and as a result different modelling approaches had to be developed. This work therefore: (1) develops additional explanatory variables for permafrost probability modelling, the most notable of which is equivalent elevation, (2) confirms the use of ground truthing as a requirement for empirical-statistical modelling in the Yukon and (3) uses a combination of models for the region in order to spatially predict between study areas. The results of this thesis will be of use to linear infrastructure route-planning, geohazard assessment and climate change adaptation strategies. Future work employing the model will allow the effects of scenario-based climate warming to be examined.

近年來因市場波動劇烈, 保險公司紛紛推出的「附保證投資型保單」, 給 予保戶在投資上的保證。然而, 附最低給付保證條件卻使得保險公司必須面 對更大的核保與財務風險。所以計算出附有最低保證條件商品的保費就顯 得格外地重要。 傳統附保證保單在訂價時,都是假設固定己知的脫退率,因為他們認為 脫退率的變化不會是影響保單價值的主因。但在Mary hardy 所著的《Investment Guarantees》一書中page 96 特別提到脫退風險: Withdrawals are more problematic. Withdrawals are, to some extent, related to the investment experience, and the withdrawal risk is, therefore, not fully diversifiable. 因此, 本文希望透過建立受經濟因子影響的解約率模型,來得到附保證保險 的風險價差。 本文考慮附保證滿期給付投資型商品(GMMB),並且使用 Heston (1993) 提出的財務市場模型以及參考Mercurio (1996,2001) 評價投資型保險之風 險承擔價差方法, 使用效用函數來描述保險契約雙方之風險趨避程度。同 時根據Kolkiewicz & Tan (2006) 假設受經濟因子的危險比率模型(hazard rate model), 來反映出資產的平均波動程度會影響保戶的脫退率。最後以 情境方式分別模擬5、10及15年到期的附保證最低滿期投資型保險之風險 價差。本研究推導之模型主要得出下列結果: (1) 保單期間愈長, 價差愈大。 (2) 價外賣權的價差高於價內。(3) 風險規避程度越高買賣價差越大。(4) 脫 退率受經濟影響愈深, 保單的買賣價差愈大。(5) 當保險公司所保證的價格 愈高時, 價差的影響愈大。 / With the fluctuation in the financial market in 2008, insurance company provided the consumers with equity-linked life insurances embedded guarantees. On the other hand, there are more risk in the financial literacy and underwriting performance of the insurance company. It is especially important to calculate the premium of the contract embedded investment guarantee properly . Traditional method of pricing the contract embedded investment guarantee was assumed that lapse rate was known, because product providers believed lapse rate was not a major factor to price the contract. However, Mary hardy’s ”Investment Guarantees” page 96 specifically mentions about the lapse rate risk: Withdrawls are more problematic. Withdrawals are, to some extent ,related to the investment experience, and the withdrawal risk is, therefore, not fully diversifiable. So this article will found the model of lapse rate dependent on economic factors and further get the fair value of one kind of a contract embedded guarantee: GMMB. We will build a financial model introduced by Heston (1993) and use the methodology provided by Mercurio (1996,2001) to price the risk bearing gap of a contract embedded guarantee with utility function to depict the risk averse level between investors . And we have lapse rates affected from the fluctuation of the implying asset which is the hazard rate model used by Kolkiewicz & Tan (2006). Finally, we will simulate a set of scenarios to present the Risk bearing spreads of equity-linked life insurance embedded guarantees whose term are 5、10 and 15 years. The following are the consequences I got: (1) The longer the duration, the larger the spread. (2) The spread out of money is larger than that in the money. (3) The higher the risk aversion, the larger the buy-ask spread. (4) The deeper the influence of economy on the lapse rate, the larger the buy-ask spread. (5) The higher guarantee price insurer offer, the deeper the spread affect.

Basal Temperature of Snow (BTS) measurements were used as the primary inputs to a high resolution (30 x 30 m grid cells) empirical-statistical regional permafrost probability model for the southern and central Yukon, and northernmost British Columbia (59° - 65°N). Data from seven individual study areas distributed across the region were combined using a blended distance decay technique, with an eighth area used for validation. The model predictions are reasonably consistent with previous permafrost maps for the area with some notable differences and a much higher level of detail. The modelling gives an overall permafrost probability of 52%. North of 62°N, permafrost becomes more extensive in the lowland areas whereas farther south permafrost is typically common only above treeline. Significant differences exist between the mountain environments of the Yukon and the Swiss Alps where the BTS method originated and as a result different modelling approaches had to be developed. This work therefore: (1) develops additional explanatory variables for permafrost probability modelling, the most notable of which is equivalent elevation, (2) confirms the use of ground truthing as a requirement for empirical-statistical modelling in the Yukon and (3) uses a combination of models for the region in order to spatially predict between study areas. The results of this thesis will be of use to linear infrastructure route-planning, geohazard assessment and climate change adaptation strategies. Future work employing the model will allow the effects of scenario-based climate warming to be examined.

本文針對附保證年金型投資商品進行評價，其中被保險人脫退因素除受到死亡解約因素之外，對經濟環境影響因素產生解約問題，如利率攀升、經濟成長率、失業率等亦須考慮。附保證年金型投資商品公帄價值為保險公司販賣投資型年金商品須對負債面進行評價，以確保被保險人之權益，保險商品價值除因投資市場環境變動造成投資商品價值累積變動之外，對於被保險人因應市場環境轉變造成脫退問題亦影響保險公司對於投資型商品準備金價值評估，本篇依照Kolkiewicz & Tan(2006)之研究，假設附保證年金型投資商品評價方式，除投資標的受到市場變動影響外，對於經濟環境變動造成被保險人解約狀況亦考慮於核保模型中，因脫退因素考慮層面過廣，故本篇主要以死亡、經濟環境變動劇烈與利率上升導致解約因素為主要考慮狀態。 本研究推導之模型主要得出下列結果：(1)附保證年金型商品的公帄價格以保險年期的影響最大，其次為風險性資本市場長期帄均波動，而死亡率影響附保證投資年金型商品主要由風險性資本市場價值決定。(2)契約初始為主要解約期間，當解約力持續增加至一定值，契約後期解約率將趨於帄坦，本研究推估契約前期經濟市場波動易造成被保險人解約狀況，故解約程度增加。(3)主要投資型商品風險價差問題影響因素為長期市場波動程度，因風險價差之衡量主要考慮風險因子變動因素導致與公帄價值或期初保費差距，依照模型假設變動因子以風險性資產價值波動程度影響最巨，其次為保險期間，因此歸納出風險價差因子主要變動來源為風險性資產價值。 / In this paper, the goal is to evaluate fair value of guaranteed annuity-type investment products. In addition to death factors, the insured terminate by other reasons, such as interest rates raising, economic growth rate, and unemployment rate. Accordance with the liabilities side, the reserve of guaranteed annuity-type investment products must match it’s fair value. There is a question how to accurately evaluate fair value of guaranteed annuity-type investment products. The price of guaranteed annuity-type investment products is affected by two parts. One is cumulative index price change in value of investment goods, the other one is withdrawal rates. Kolkiewicz & Tan’s research assume guaranteed annuity-type investment products evaluation methods which is affected by market environment and termination status of the insured. The results show that (1) The major impact on fair value of guaranteed annuity-type investment products is mainly from the period of the insurance contracts. The secondary effect is long-term average risk capital market volatility. (2) The main terminate time is the beginning of the contracts. When the lapse rates continued to increase to a certain value, lapse rate tends to smooth.(3) The major impact on risk spread of guaranteed annuity-type investment products is mainly from long-term market volatility. To sum up, the major changes in sources of risk spreads factor are from asset value.

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